Concomitant Effect of Quercetin and Its Copper Complex in the Development of Sustained-Release Nanoparticles of Polycaprolactone, Used for the Treatment of Skin Infection

The study aimed to improve the treatment of impetigo with naturally occurring quercetin and its copper-quercetin (Cu-Q) complex by preparing sustained-release (SR) nanoparticles of polycaprolactone (PCL). The solvent evaporation method was used for the copper-quercetin (Cu-Q) complex formation, and their PCL nanoparticles (PCL-NPs, Q-PCL-NPs, and Cu-Q-PCL-NPs) were prepared by the high-pressure homogenization method. Synthesis of nanoparticles was confirmed by their physicochemical and antibacterial properties of quercetin against Gram-positive as well as Gram-negative bacteria. The percentage loading efficiency of quercetin and release in 100 mM of phosphate buffer pH 7.4 and 5.5 at 37 °C was found to be more than 90% after 24 h with the zero-order release pattern. Minimum inhibitory concentration of nanoparticles was found to increase threefold in the case of Cu-Q-PCL-NPs may be due to the synergistic antibacterial behavior. Scanning electron microscopy showed spherical nanoparticles, and surface roughness was confirmed by atomic force microscopy analysis. Fortunately, no sign of irritation on rat skin even at 3%, was seen. In vitro antioxidant assay by 2,2-diphenyl-1-picrylhydrazyl reduction was found to be ≤80 ± 0.02% which confirmed their scavenging activity. Interestingly, for the ex vivo study, the tape-stripping model was applied against Staphylococcus aureus containing rats and showed the formation of the epidermal layer within 4-5 days. Confirmation of antibacterial activity of pure quercetin, from Cu-Q complex, and their SR release from Q-PCL-NPs and Cu-Q-PCL-NPs was considered an effective tool for the treatment of skin diseases and can be used as an alternative of already resistant ciprofloxacin in impetigo.

Machine learning predictive performance evaluation of conventional and fuzzy radiomics in clinical cancer imaging cohorts

BACKGROUND

Hybrid imaging became an instrumental part of medical imaging, particularly cancer imaging processes in clinical routine. To date, several radiomic and machine learning studies investigated the feasibility of in vivo tumor characterization with variable outcomes. This study aims to investigate the effect of recently proposed fuzzy radiomics and compare its predictive performance to conventional radiomics in cancer imaging cohorts. In addition, lesion vs. lesion+surrounding fuzzy and conventional radiomic analysis was conducted.

METHODS

Previously published 11C Methionine (MET) positron emission tomography (PET) glioma, 18F-FDG PET/computed tomography (CT) lung, and 68GA-PSMA-11 PET/magneto-resonance imaging (MRI) prostate cancer retrospective cohorts were included in the analysis to predict their respective clinical endpoints. Four delineation methods including manually defined reference binary (Ref-B), its smoothed, fuzzified version (Ref-F), as well as extended binary (Ext-B) and its fuzzified version (Ext-F) were incorporated to extract imaging biomarker standardization initiative (IBSI)-conform radiomic features from each cohort. Machine learning for the four delineation approaches was performed utilizing a Monte Carlo cross-validation scheme to estimate the predictive performance of the four delineation methods.

RESULTS

Reference fuzzy (Ref-F) delineation outperformed its binary delineation (Ref-B) counterpart in all cohorts within a volume range of 938-354987 mm³ with relative cross-validation area under the receiver operator characteristics curve (AUC) of  +4.7-10.4. Compared to Ref-B, the highest AUC performance difference was observed by the Ref-F delineation in the glioma cohort (Ref-F: 0.74 vs. Ref-B: 0.70) and in the prostate cohort by Ref-F and Ext-F (Ref-F: 0.84, Ext-F: 0.86 vs. Ref-B: 0.80). In addition, fuzzy radiomics decreased feature redundancy by approx. 20%.

CONCLUSIONS

Fuzzy radiomics has the potential to increase predictive performance particularly in small lesion sizes compared to conventional binary radiomics in PET. We hypothesize that this effect is due to the ability of fuzzy radiomics to model partial volume effects and delineation uncertainties at small lesion boundaries. In addition, we consider that the lower redundancy of fuzzy radiomic features supports the identification of imaging biomarkers in future studies. Future studies shall consider systematically analyzing lesions and their surroundings with fuzzy and binary radiomics.

Antibiograms of Gut Flora of Poultry Farms Workers Reveal Higher Resistance Levels as Compared to Non-Workers

Introduction

Antibiotics are being used in humans and animals for treatment and control of bacterial infections. Excessive use of antibiotics in the production of poultry is a popular practice, but it poses serious health issues by transferring resistance from farm to humans via food or direct exposure.

Study Objective

The objective of this study was to carry out a comparison of the resistance and sensitivity profile of isolated isolates from sewage of toilets that were in use of workers inside the farm and from sewage of household toilets.

Methodology

In this study, a total of 320 sewage samples were collected. The antibiotic susceptibility profile was checked by Kirby-Bauer disc diffusion method, and the statistical analysis was carried out by MS excel. Chi-square test was performed to determine whether the antibiograms from two sample types were statistically different from each other or not.

Results

From 320 sewage samples, a total of 296 bacterial isolates were isolated among which the leading bacterium was E. coli. The proportion of resistance, ESBL production and MDR was significantly higher in bacteria isolated from sewage of toilets under use of poultry farm workers as compared to the sewage from domestic use toilets.

Conclusion

Resistance significantly increased in the bacteria isolated from toilets under use of poultry farm workers as compared to the ones isolated from control sewage samples.

Methyl Jasmonate Alleviated the Adverse Effects of Cadmium Stress in Pea (Pisum sativum L.): A Nexus of Photosystem II Activity and Dynamics of Redox Balance

The accumulation of cadmium (Cd) in leaves reduces photosynthetic capacity by degrading photosynthetic pigments, reducing photosystem II activity, and producing reactive oxygen species (ROS). Though it was demonstrated that the application of Methyl Jasmonate (MeJA) induces heavy metal (HM) stress tolerance in plants, its role in adjusting redox balance and photosynthetic machinery is unclear. In this study, the role of MeJA in modulating photosystem II (PSII) activity and antioxidant defense system was investigated to reduce the toxic effects of Cd on the growth of pea (Pisum sativum L.) cultivars. One-week-old seedlings of three pea varieties were subjected to Cd stress (0, 50, 100 μm), and MeJA (0, 1, 5, 10 μm) was applied as a foliar spray for 2 weeks. Cadmium stress reduced the growth of all three pea varieties. Cadmium stress decreased photosynthetic pigments [Chl a (58.15%), Chl b (48.97%), total Chl (51.9%) and carotenoids (44.01%)] and efficiency of photosystem II [Fv/Fm (19.52%) and Y(II; 67.67%)], while it substantially increased Cd accumulation along with an increase in ROS (79.09%) and lipid peroxidation (129.28%). However, such adverse effects of Cd stress varied in different pea varieties. Exogenous application of MeJA increased the activity of a battery of antioxidant enzymes [superoxide dismutase (33.68%), peroxidase (29.75%), and catalase (38.86%)], improved photosynthetic pigments and PSII efficiency. This led to improved growth of pea varieties under Cd stress, such as increased fresh and dry weights of shoots and roots. In addition, improvement in root biomass by MeJA was more significant than that of shoot biomass. Thus, the mitigating effect of MeJA was attributed to its role in cellular redox balance and photosynthetic machinery of pea plants when exposed to Cd stress.

Two-Component System Genes in Sorghum bicolor: Genome-Wide Identification and Expression Profiling in Response to Environmental Stresses

The two-component signal transduction system (TCS) acts in a variety of physiological processes in lower organisms and has emerged as a key signaling system in both prokaryotes and eukaryotes, including plants. TCS genes assist plants in processes such as stress resistance, cell division, nutrition signaling, leaf senescence, and chloroplast division. In plants, this system is composed of three types of proteins: response regulators (RRs), histidine kinases (HKs), and histidine phosphotransfer proteins (HPs). We aimed to study the Sorghum bicolor genome and identified 37 SbTCS genes consisting of 13 HKs, 5 HPs, and 19 RRs (3 type-A RRs, 7 type-B RRs, 2 type-C RRs, and 7 pseudo-RRs). The structural and phylogenetic comparison of the SbTCS members with their counterparts in Arabidopsis thaliana, Oryza sativa, Cicer arietinum, and Glycine max showed group-specific conservations and variations. Expansion of the gene family members is mostly a result of gene duplication, of both the tandem and segmental types. HKs and RRs were observed to be originated from segmental duplication, while some HPs originated from tandem duplication. The nuclear genome of S. bicolor contain 10 chromosomes and these SbTCS genes are randomly distributed on all the chromosomes. The promoter sequences of the SbTCS genes contain several abiotic stress-related cis-elements. RNA-seq and qRT-PCR-based expression analysis demonstrated most of the TCS genes were responsive to drought and salt stresses in leaves, which suggest their role in leaf development. This study lays a foundation for further functional study of TCS genes for stress tolerance and developmental improvement in S. bicolor.

UK and Ireland survey of MPharm student and staff experiences of mental health curricula, with a focus on Mental Health First Aid

Background

One in four people experience a mental health problem every year and improving mental health care is an international priority. In the course of their work, pharmacists frequently encounter people with mental health problems. The experience of mental health teaching, including Mental Health First Aid (MHFA) training, in undergraduate pharmacy (MPharm) students in the UK and Ireland is not well documented. Students’ viewpoints, contextualised with curricular overviews provided by staff, were analysed to understand their experience.

Methods

An anonymous, online questionnaire was distributed to MPharm students and staff in the UK and Ireland. Students were asked closed questions regarding their course and exposure to MHFA, which were analysed using descriptive statistics. Open questions were included to enable explanations and these data were used to contextualise the quantitative findings. One member of staff from each university was invited to answer a modified staff version of the questionnaire, to provide a curriculum overview and staff perspective.

Results

232 students and 13 staff, from 22 universities, responded. Three-quarters of students did not agree with the statement that ‘mental health was embedded throughout the MPharm’. Most students (80.6%) stated that they were taught neuropharmacology whilst 44.8% stated that their course included communicating with people about their mental health. One-third (33.2%) of students stated that their degree ‘adequately prepared them to help people with their mental health’. Twenty-six students (11.6%) had completed MHFA training of which 89% would endorse inclusion of this within the MPharm. Of those who had not completed the training, 81% expressed a desire to do so. Those who completed MHFA training self-reported greater preparedness than those who did not, but student numbers were small.

Conclusions

Mental health teaching for pharmacy undergraduates is more focussed on theoretical aspects rather than applied skills. MHFA was viewed by students as one way to enhance skill application. The association of the increased self-reported preparedness of those who completed MHFA could be confounded by a positive environmental cultural. MPharm programmes need sufficient focus on real-world skills such as communication and crisis response, to complement the fundamental science.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40545-021-00364-1.

376 Factors Affecting Female Medical Student Interest in Surgery - A Nationwide Cross-Sectional Survey

Introduction

We aim to elucidate female student interest in Surgery and factors that are deterring students from considering a surgical career. With this information, we can evaluate if there are changes that can be made within medical education.

Method

A cross-sectional online survey was distributed via LimeSurvey to medical students across 33 UK medical schools. Our survey assessed student interest in a surgical career, personal experience on clinical placements, and what attracts or dissuades students from a surgical career.

Results

211 student responses were collected. 57% of students indicated an interest in Surgery. 55% of female and 63% of male students expressed surgical interest. 65.7% of second-year students indicated surgical interest, compared to 54.3% of students in final year; a 17.35% decrease. When asked, 88% of students believe there is disproportionate female to male surgeons.

Conclusions

Although our survey revealed that there is a healthy interest in Surgery, the number of women considering Surgery continues to dwindle throughout training, leading to massive discrepancy. It is paramount that there are both male and female mentors for students to visualise that there are no limitations for women in the field of Surgery.

Mental health curricula and Mental Health First Aid in the MPharm

Introduction

Improving mental health care is an international priority, and one that is championed by the Royal Pharmaceutical Society. (1) In the course of their work, pharmacists frequently encounter people with mental health problems. The extent to which mental health is taught on the undergraduate pharmacy degree in the UK and Ireland, and the inclusion of Mental Health First Aid (MHFA) training, has not be described recently.

Aim

We aimed to determine how mental health teaching is embedded into the MPharm and students’ perception of their own preparedness to help people with their mental health. We explored if and how MHFA training is included, and students’ experience of, or desire to complete this.

Methods

We conducted an anonymous, online questionnaire of UK and Ireland MPharm students, distributed via networks and social media. Students were asked a series of closed questions about mental health teaching in the MPharm, and exposure to MHFA. We analysed answers using descriptive statistics. We included some open-ended questions to enable students to expand on their answers. We used this qualitative data to contextualize findings. We invited one member of staff from each university to answer a modified staff version of the questionnaire, in order to provide a curriculum overview and staff perspective on MHFA provision.

Results

232 students and 13 staff responded, from 22 universities in total. Eighty percent of student participants were female and 70% were in the third or final year of study. Three-quarters of students felt that mental health was not embedded throughout the MPharm. Eighty-percent of students stated that they were taught about neuropharmacology and 44.8% stated that their course included communicating with people about their mental health. One third of students felt that their degree adequately prepared them to help people with their mental health. Twenty-six students (11.6%) had completed MHFA training of which 89% would endorse inclusion of this within the MPharm. Of those who had not completed the training, 81% expressed a desire to do so. Those who completed MHFA training self-reported more preparedness than those who did not, but student numbers were small.

Conclusion

Mental health teaching remains focused on theoretical aspects, such as pharmacology, with less emphasis on practical skills, such as communication skills that might support interactions about mental health. MHFA was viewed by students as one way to enhance this. Of the small number of students who had completed MHFA, they displayed an increased self-reported preparedness. This could, however, be linked to the environmental culture of the programme rather than the training per se. MPharm programmes need sufficient focus on skills including communication and crisis response that may be required by pharmacists, alongside the fundamental scientific knowledge relating to mental health.

References

1. Royal Pharmaceutical Society. No health without mental health: How can pharmacy support people with mental health problems? London: RPS; 2018.

Antibacterial activity and characterization of zinc oxide nanoparticles synthesized by microalgae

Biosynthesis of zinc oxide nanoparticles (ZnO-NPs) using microalgae is novel and cost-effective approach. We studied production, molecular characterization, and antibacterial activity. Filtrates of isolated microalgae strain ZAA1 (MF140241), ZAA2 (MF114592) and ZAA3 (MF114594) were used. Incubation of these strains in 5mM solution of zinc nitrate was resulted in the synthesis of ZnO-NPs. Fourier-transform infrared, UV-visible spectroscopy and scanning electron microscopy were used to characterize the nanoparticles. Significant antibacterial activity of ZnO-NPs was measured against Escherichia coli, Staphylococcus aureus, Micrococcus luteus, Klebsiella pneumoniae and Citrobacter freundii. The microalgae mediated ZnO-NPs production is a successful procedure that can be used in a wide range of biomedical applications.

Artificial Neural Network (ANN) Approach to Predict an Optimized pH-Dependent Mesalamine Matrix Tablet

Background

Severe bleeding and perforation of the colon and rectum are complications of ulcerative colitis which can be treated by a targeted drug delivery system.

Purpose

Development of colon-targeted delivery usually involves a complex formulation process and coating steps of pH-sensitive methacrylic acid based Eudragit^®. The current work was purposefully designed to develop dicalcium phosphate (DCP) facilitated with Eudragit-S100-based pH-dependent, uncoated mesalamine matrix tablets.

Materials and Methods

Mesalamine formulations were compressed using wet granulation technique with varying compositions of dicalcium phosphate (DCP) and Eudragit-S100. The developed formulations were characterized for physicochemical and drug release profiles. Infrared studies were carried out to ensure that there was no interaction between active ingredients and excipients. Artificial neural network (ANN) was used for the optimization of final DCP-Eudragit-S100 complex and the experimental data were employed to train a multi-layer perception (MLP) using quick propagation (QP) training algorithm until a satisfactory root mean square error (RMSE) was reached. The ANN-aided optimized formulation was compared with commercially available Masacol^®.

Results

Compressed tablets met the desirability criteria in terms of thickness, hardness, weight variation, friability, and content uniformity, ie, 5.34 mm, 7.7 kg/cm^2, 585±5 mg (%), 0.44%, and 103%, respectively. In-vitro dissolution study of commercially available mesalamine and optimized formulation was carried out and the former showed 100% release at 6 h while the latter released only 12.09% after 2 h and 72.96% after 12 h which was fitted to Weibull release model with b value of 1.3, indicating a complex release mechanism.

Conclusion

DCP-Eudragit-S100 blend was found explicative for mesalamine release without coating in gastric and colonic regions. This combination may provide a better control of ulcerative colitis.

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Influence of single-nucleotide polymorphisms in the IFNG towards susceptibility to tuberculosis in a Pakistani population

Tuberculosis (TB) is a global issue as one-third of the population worldwide is considered to be infected. TB has become a critical public health problem as a result of increasing drug resistance, which poses a challenge to current control strategies. Similar to environmental factors, genetic makeup of the host equally contributes to disease onset. We performed genotypic analysis to examine the relationship between IFNG and TB onset and drug resistance in a Pakistani population comprising 689 subjects. Notable differences were observed in the IFNG polymorphism (+874T/A) between the case and control groups. The frequency of the wild-type genotype (TT) in the controls (43.2%) was significantly higher than in the cases (25.3%) (odds ratio [OR] = 0.77, p < 0.0001), while the mutant genotype frequency (AA) (38.57%) in the cases was significantly higher than in the controls (22.6%) (OR = 1.46, p < 0.0001). The heterozygous genotype frequency (TA) did not significantly differ between the control and case groups. Compared with the controls, the variant allele (A) was approximately twice as frequent in the cases. Females and older people have a higher chance of disease development. Finally, the IFNG (+874T/A) polymorphism was not associated with drug sensitivity or resistance. However, a genotypic polymorphism of IFNG (+874T/A) was significantly associated with susceptibility to TB, and the T allele conferred protection against TB. Additional studies involving larger cohorts are needed to further explore this relationship between genetics and disease vulnerability.

An Overview of the Genetics of Plant Response to Salt Stress: Present Status and the Way Forward

Salinity is one of the major threats faced by the modern agriculture today. It causes multidimensional effects on plants. These effects depend upon the plant growth stage, intensity, and duration of the stress. All these lead to stunted growth and reduced yield, ultimately inducing economic loss to the farming community in particular and to the country in general. The soil conditions of agricultural land are deteriorating at an alarming rate. Plants assess the stress conditions, transmit the specific stress signals, and then initiate the response against that stress. A more complete understanding of plant response mechanisms and their practical incorporation in crop improvement is an essential step towards achieving the goal of sustainable agricultural development. Literature survey shows that investigations of plant stresses response mechanism are the focus area of research for plant scientists. Although these efforts lead to reveal different plant response mechanisms against salt stress, yet many questions still need to be answered to get a clear picture of plant strategy to cope with salt stress. Moreover, these studies have indicated the presence of a complicated network of different integrated pathways. In order to work in a progressive way, a review of current knowledge is critical. Therefore, this review aims to provide an overview of our understanding of plant response to salt stress and to indicate some important yet unexplored dynamics to improve our knowledge that could ultimately lead towards crop improvement.

Impact of motion compensation and partial volume correction for 18F-NaF PET/CT imaging of coronary plaque

Recent studies have suggested that ¹⁸F-NaF-PET enables visualization and quantification of plaque micro-calcification in the coronary tree. However, PET imaging of plaque calcification in the coronary arteries is challenging because of the respiratory and cardiac motion as well as partial volume effects. The objective of this work is to implement an image reconstruction framework, which incorporates compensation for respiratory as well as cardiac motion (MoCo) and partial volume correction (PVC), for cardiac ¹⁸F-NaF PET imaging in PET/CT. We evaluated the effect of MoCo and PVC on the quantification of vulnerable plaques in the coronary arteries. Realistic simulations (Biograph TPTV, Biograph mCT) and phantom acquisitions (Biograph mCT) were used for these evaluations. Different uptake values in the calcified plaques were evaluated in the simulations, while three 'plaque-type' lesions of 36, 31 and 18 mm³ were included in the phantom experiments. After validation, the MoCo and PVC methods were applied in four pilot NaF-PET patient studies. In all cases, the MoCo-based image reconstruction was performed using the STIR software. The PVC was obtained from a local projection (LP) method, previously evaluated in preclinical and clinical PET. The results obtained show a significant increase of the measured lesion-to-background ratios (LBR) in the MoCo  +  PVC images. These ratios were further enhanced when using directly the tissue-activities from the LP method, making this approach more suitable for the quantitative evaluation of coronary plaques. When using the LP method on the MoCo images, LBR increased between 200% and 1119% in the simulated data, between 212% and 614% in the phantom experiments and between 46% and 373% in the plaques with positive uptake observed in the pilot patients. In conclusion, we have built and validated a STIR framework incorporating MoCo and PVC for ¹⁸F-NaF PET imaging of coronary plaques. First results indicate an improved quantification of plaque-type lesions.

Influence of sub-lethal crude oil concentration on growth, water relations and photosynthetic capacity of maize (Zea mays L.) plants

Maize tolerance potential to oil pollution was assessed by growing Zea mays in soil contaminated with varying levels of crude oil (0, 2.5 and 5.0 % v/w basis). Crude oil contamination reduced soil microflora which may be beneficial to plant growth. It was observed that oil pollution caused a remarkable decrease in biomass, leaf water potential, turgor potential, photosynthetic pigments, quantum yield of photosystem II (PSII) (Fv/Fm), net CO2 assimilation rate, leaf nitrogen and total free amino acids. Gas exchange characteristics suggested that reduction in photosynthetic rate was mainly due to metabolic limitations. Fast chlorophyll a kinetic analysis suggested that crude oil damaged PSII donor and acceptor sides and downregulated electron transport as well as PSI end electron acceptors thereby resulting in lower PSII efficiency in converting harvested light energy into biochemical energy. However, maize plants tried to acclimate to moderate level of oil pollution by increasing root diameter and root length relative to its shoot biomass, to uptake more water and mineral nutrients.

Heterosis and correlation in interspecific and intraspecific hybrids of cotton

Interspecific and intraspecific hybrids show varying degrees of heterosis for yield and yield components. Yield-component traits have complex genetic relationships with each other. To determine the relationship of yield-component traits and fiber traits with seed cotton yield, six lines (Bt. CIM-599, CIM-573, MNH-786, CIM-554, BH-167, and GIZA-7) and three test lines (MNH-886, V4, and CIM-557) were crossed in a line x tester mating design. Heterosis was observed for seed cotton yield, fiber traits, and for other yield-component traits. Heterosis in interspecific hybrids for seed cotton yield was more prominent than in intraspecific hybrids. The interspecific hybrid Giza-7 x MNH-886 had the highest heterosis (114.77), while among intraspecific hybrids, CIM-554 x CIM-557 had the highest heterosis (61.29) for seed cotton yield. A major trait contributing to seed cotton yield was bolls/plant followed by boll weight. Correlation studies revealed that bolls/plant, boll weight, lint weight/boll, lint index, seed index, lint/seed, staple length, and staple strength were significantly and positively associated with seed cotton yield. Selection based on boll weight, boll number, lint weight/boll, and lint index will be helpful for improving cotton seed yield.

A simple UV-ozone surface treatment to enhance photocatalytic performance of TiO2 loaded polymer nanofiber membranes

UV-ozone treated electrospun nanofiber membranes for increased photocatalytic activity.

There's more to the picture than meets the eye: nitric oxide cross talk with Ca2+ signaling

Calcium and nitric oxide (NO) are two important biological messengers. Increasing evidence indicates that Ca(2+) and NO work together in mediating responses to pathogenic microorganisms and microbe-associated molecular patterns. Ca(2+) fluxes were recognized to account for NO production, whereas evidence gathered from a number of studies highlights that NO is one of the key messengers mediating Ca(2+) signaling. Here, we present a concise description of the current understanding of the molecular mechanisms underlying the cross talk between Ca(2+) and NO in plant cells exposed to biotic stress. Particular attention will be given to the involvement of cyclic nucleotide-gated ion channels and Ca(2+) sensors. Notably, we provide new evidence that calmodulin might be regulated at the posttranslational level by NO through S-nitrosylation. Furthermore, we report original transcriptomic data showing that NO produced in response to oligogalacturonide regulates the expression of genes related to Ca(2+) signaling. Deeper insight into the molecules involved in the interplay between Ca(2+) and NO not only permits a better characterization of the Ca(2+) signaling system but also allows us to further understand how plants respond to pathogen attack.

Study of oligogalacturonides-triggered nitric oxide (NO) production provokes new questioning about the origin of NO biosynthesis in plants

We investigated the production and function of nitric oxide (NO) in Arabidopsis thaliana leaf discs as well as whole plants elicited by oligogalacturonides (OGs). Using genetic, biochemical and pharmacological approaches, we provided evidence that OGs induced a Nitrate Reductase (NR)-dependent NO production together with an increased NR activity and NR transcripts accumulation. In addition, NO production was sensitive to the mammalian NOS inhibitor L-NAME. Intriguingly, L-NAME impaired OG-induced NR activity and did not further affect the remaining OG-induced NO production in the nia1nia2 mutant. These data suggest that the L-arginine and NR pathways, co-involved in NO production, do not work independently. Taking account these new data, we propose scenarios to explain NO production in response to biotic stress.

Nitric oxide production mediates oligogalacturonide-triggered immunity and resistance to Botrytis cinerea in Arabidopsis thaliana

Nitric oxide (NO) regulates a wide range of plant processes from development to environmental adaptation. In this study, we investigated the production and/or function of NO in Arabidopsis thaliana leaf discs and plants elicited by oligogalacturonides (OGs) and challenged with Botrytis cinerea. We provided evidence that OGs triggered a fast and long lasting NO production which was Ca(2+) dependent and involved nitrate reductase (NR). Accordingly, OGs triggered an increase of both NR activity and transcript accumulation. NO production was also sensitive to the mammalian NO synthase inhibitor L-NAME. Intriguingly, we showed that L-NAME affected NO production by interfering with NR activity, thus questioning the mechanisms of how this compound impairs NO synthesis in plants. We further demonstrated that NO modulates RBOHD-mediated reactive oxygen species (ROS) production and participates in the regulation of OG-responsive genes such as anionic peroxidase (PER4) and a β-1,3-glucanase. Mutant plants impaired in PER4 and β-1,3-glucanase, as well as Col-0 plants treated with the NO scavenger cPTIO, were more susceptible to B. cinerea. Taken together, our investigation deciphers part of the mechanisms linking NO production, NO-induced effects and basal resistance to B. cinerea.

S-nitrosylation: an emerging post-translational protein modification in plants

Increasing evidences support the assumption that nitric oxide (NO) acts as a physiological mediator in plants. Understanding its pleiotropic effects requires a deep analysis of the molecular mechanisms underlying its mode of action. In the recent years, efforts have been made in the identification of plant proteins modified by NO at the post-translational level, notably by S-nitrosylation. This reversible process involves the formation of a covalent bond between NO and reactive cysteine residues. This research has now born fruits and numerous proteins regulated by S-nitrosylation have been identified and characterized. This review describes the basic principle of S-nitrosylation as well as the Biotin Switch Technique and its recent adaptations allowing the identification of S-nitrosylated proteins in physiological contexts. The impact of S-nitrosylation on the structure/function of selected proteins is further discussed.

Allogeneic bone marrow transplantation in beta-thalassaemia--single centre study

OBJECTIVE

To evaluate outcome of allogeneic BMT in beta-Thalassaemia at the Armed Forces Bone Marrow Transplant Centre, Rawalpindi, Pakistan from August 2001 to November 2003.

METHODS

Nineteen patients with beta-Thalassaemia underwent allogeneic BMT/PBSC transplantation from HLA identical sibling donors. Patients were classified in three groups according to Pesaro (Italy) risk classification. Class-I (n = 9) and Class-II (n = 7) patients received conditioning with busulphan/cyclophosphamide, whereas Class-III (n = 3) patient received conditioning with hydroxyurea, azathioprine, fludarabine, along with Bu14 / Cy 200. Cyclosporine, prednisolone and methotrexate were given for GvHD prophylaxis. Stem cells dose infused was >4.0 x 10(8)/kg body weight of the patient.

RESULTS

Engraftment was achieved in all Class-I patients, whereas in Class-II and Class-III , graft rejection was observed in one patient from each class. Median time to achieve absolute neutrophil recovery (> 0.5 x 10(9)/l) was 13 days, platelet count (> 20 x 10(9)/1) was 15 days and reticulocyte count (>0.5%) was 15 days. Acute GvHD was observed in 15 patients. One patient developed grade IV GvHD (liver and skin) and died within 30 days post BMT. Post transplant infectious complications were pseudomonas septicemia, disseminated fungal infection, CMV pneumonia and tuberculosis. Three patients died of these complications during post transplant period (31-90 days). Median stay in hospital was 25 days.

CONCLUSION

Allogeneic BMT is the only curative therapy for beta-Thalassaemia patients, however the success rate can be increased if the patients are selected carefully and transplanted at an early age.

The safety of epidural analgesia in labour and its effect on delivery--a case control study in Pakistani women

To assess the safety and effect of epidural analgesia on the course of labour and delivery in Pakistani women, a retrospective case control study was conducted from November, 1986 to November, 1991 (5 years) at the Aga Khan University Medical Centre, Karachi. All patients (n = 64) who received epidural analgesia for labour (cases) were compared with randomly selected patients (n = 18) who did not receive epidural analgesia during labour (controls). The cases and controls were matched for age, height, body mass index, parity, use of oxytocin, presentation and weight of the foetus. There was no significant difference (P > 0.05) between the two groups in duration of labour, caesarean section rate and foetal apgar scores at 1 and 5 minutes after birth. The incidence of malposition of foetal vertex at delivery and that of instrumental (forceps) deliveries was significantly higher (P < 0.05 and < 0.01 respectively) in the epidural group as compared to controls. The incidence of complications was low and the acceptance and tolerance of epidural analgesia was good in our patients.

Experience with screening for abnormal glucose tolerance in pregnancy: maternal and perinatal outcome

In order to determine the prevalence of glucose intolerance in pregnancy, 2,230 consecutive women attending the antenatal clinic at the Aga Khan University Medical Centre in Karachi, Pakistan were subjected on the first antenatal visit, irrespective of gestational age, to a 75 g glucose challenge followed 2 hr later by plasma glucose determination. The test, was repeated at 28-32 weeks of gestation for those patients who had an abnormal initial screen at less than 28 weeks gestation followed by a normal glucose tolerance test and for those who had a risk factor for gestational diabetes even though the initial screen at less than 28 weeks gestation was normal. The initial glucose challenge test was abnormal (2 hr plasma glucose greater than 140 mg%) in 8.6% of the screened population. An oral glucose tolerance test on these patients revealed a prevalence for the entire population of 3.5% of gestational diabetes and 1.9% of impaired glucose tolerance test based on the modified O'Sullivan criteria. Patients with abnormal glucose tolerance test were older, had higher parity, a past history of macrosomia and a family history of diabetes compared to the controls. These patients also had a higher incidence of preterm labour and caesarean section. In the neonates hypoglycemia and hyperbilirubinemia were similarly higher. The fetal abnormality rate was 5.6% and the perinatal mortality was 28/1,000 which were higher than the controls.

Cervical cancer screening program in a Muslim country: three-year experience at the Aga Khan University Medical Center, Karachi

A systematic cervical cancer screening program was initiated in January 1987 at The Aga Khan University Medical Center, Karachi, Pakistan. The 8,784 cervical smears obtained in 3 subsequent years from 8,412 consecutive women attending the gynecology and antenatal clinics were reviewed. "Positive" smears were found in 111 (1.3%) patients; 107 (1.27%) smears showed squamous epithelial dysplasia and 4 smears showed adenocarcinoma. The highest incidence of abnormal smears was found in the 45-54 years age group. Colposcopy and biopsy was performed on all patients with "positive" smears except on those with atypical or mildly dysplastic ones, in whom only the persistence of the abnormality on repeated smears was considered an indication for tissue evaluation. The histopathologic diagnosis of these biopsy specimens revealed cervical intra-epithelial neoplasia in 60 patients and invasive cervical cancer in 6 patients.

Rubella susceptibility and continuing risk of infection in pregnancy

Sera of 2000 pregnant women attending the antenatal clinic of the Aga Khan University Hospital were tested for rubella antibodies. Of these 1684 (84.2%) were immune and 316 (15.8%) were susceptible to rubella. Majority (99.8%) of the women were Asian in origin. Susceptibility decreased with increasing age and parity. We conclude that apart from vaccination of all young children greater attention should be paid to immunization of women of child-bearing age.

[Treatment of penetrating wounds of the heart]

An analysis of results of treatment of 43 victims with knife and gunshot wounds of the heart has shown that treatment of the trauma disease in these patients is dependent on the trauma mechanism, character and localization of the myocardium wounds and intensity of bleeding. These factors taken into consideration will improve results of the treatment. General lethality among patients with injuries of the heart made up 25.5%.