Fine mapping of a new common bean anthracnose resistance gene (Co-18) to the proximal end of Pv10 in Indian landrace KRC-5

KEY MESSAGE

Mapping and fine mapping of bean anthracnose resistance genes is a continuous process. We report fine mapping of anthracnose resistance gene Co-18 which is the first anthracnose gene mapped to Pv10. The discovery of resistance gene is a major gain in the bean anthracnose pathosystem research. Among the Indian common bean landraces, KRC-5 exhibit high levels of resistance to the bean anthracnose pathogen Colletotrichum lindemuthianum. To precisely map the anthracnose resistance gene, we used a Recombinant Inbred Line (F2:9 RIL) population (KRC-5 × Jawala). The inheritance test revealed that KRC-5 carries a dominant resistance gene temporarily designated as Co-18. We discovered two RAPD markers linked to Co-18 among 287 RAPD markers. These RAPD markers were eventually developed into SCARs (Sc-OPR15 and Sc-OPF6) and flank Co-18 on chromosome Pv10 at a distance of 5.3 and 4.2 cM, respectively. At 4.0-4.1 Mb on Pv10, we detected a SNP (single-nucleotide polymorphism) signal. We synthesized 58 SSRs and 83 InDels from a pool of 135 SSRs and 1134 InDels, respectively. Five SSRs, four InDels, and two SCARs were used to generate the high-density linkage map, which led to the identification of two SSRs (SSR24 and SSR36) that are tightly linked to Co-18. These two SSRs flank the Co-18 to 178 kb genomic region with 13 candidate genes including five NLR (nucleotide-binding and leucine-rich repeat) genes. The closely linked markers SSR24 and SSR36 will be used in cloning and pyramiding of the Co-18 gene with other R genes to develop durable resistant bean varieties.

Deletions of SMNI gene exon 7 and NAIP gene exon 5 in spinal muscular atrophy patients in selected population

OBJECTIVE

Spinal muscular atrophy (SMA) is common among various populations because the genetic makeup is monogamous due to consanguineous marriages. Two genes, i.e., survival motor neuron (SMN1) and neuronal apoptosis inhibitory protein (NAIP) are mapped to the SMA vicinity of chromosome 5q13. The main objective of the study was to develop a solitary advanced genetic tool for the diagnosis of SMA by using SMN1 gene exon 7 and NAIP gene exon 5.

PATIENTS AND METHODS

This study involved SMA patients (n=84) belonging to different clinical features and socio-economic status. The identity of the intact NAIP gene is primarily based on the amplification of exon 5 only in those SMA patients that have a deletion of SMN1 gene exon 7. Healthy controls (n=84) were also included in this study. The mutational analysis was observed through the Sanger sequencing method, where chromatograms were observed by using Chromas version 2.6.0.

RESULTS

This study showed a higher prevalence of SMA in females than in males. NAIP gene is considered a phenotype modifier as most SMA patients (94.90%) have SMN1 exon 7 deletion along with a deletion in exon 5 of the NAIP gene. Single nucleotide conversion C-T in exon 7 of SMN1 gene leads to its complete deletion. Mutated proteins encoded by SMN1 and NAIP genes also result in degeneration and muscle weakness in SMA patients.

CONCLUSIONS

These SMA-associated gene deletions can be used as a molecular evaluation tool for pre- and postnatal diagnosis of SMA. This will be valuable when there is a need for precise and consistent results with a strong focus on quantification.

Silver diamine fluoride: A stem cell cytotoxicity and dentin growth factor release in-vitro study

AIM

To investigate the effect of 38% SDF and its serial dilutions on the Stem cells from Human Exfoliated Deciduous teeth (SHED) and its ability to release growth factors from deciduous dentine.

METHODS

The viability of SHED post-exposure to 38%, 3.8%, 0.38%, 0.038%, and 0.0038% SDF were assessed at 2, 5, and 7 days using the CyQuant assay, and results were validated using the MTT assay. The osteogenic differentiation of the cells was also investigated post-exposure to 0.0038% SDF. The release of the growth factors; TGF-β1, FGF-b, BMP-2, and VEGF from deciduous dentin discs exposed to 38% SDF, 0.0038% SDF, Ca(OH)2, MTA, and 17% EDTA were examined using ELISA. Statistical analysis was performed using means and standard deviations (p < 0.05). Two-way ANOVA compared the means of more than two groups with Tukey's multiple comparison test. The unpaired t-test was also used to compare the differences between the two data sets.

CONCLUSION

38% SDF released dentinogenic growth factors from dentin discs, potentially explaining its role in reactionary dentinogenesis. Moreover, 0.0038% SDF resulted in a non-cytotoxic concentration that enhanced cellular proliferation and released bioactive molecules from dentin comparable to the 38% concentration. After further investigations, the 0.0038% dilution of SDF could present itself as a clinical concentration.

COVID-19: how prepared are front-line healthcare workers in England?

National efforts are underway to prepare the UK National Health Service (NHS) for the COVID-19 pandemic; however, the efficacy of these interventions is unknown. In view of this, a cross-sectional survey of front-line healthcare workers (HCWs) at two large acute NHS hospital trusts in England was undertaken to assess their confidence and perceived level of preparedness for the virus. The survey found that there has been moderate success in readying HCWs to manage COVID-19, but that more still needs to be done, particularly in relation to educating HCWs about laboratory diagnostics.

Critical points in the pathway of antibiotic prescribing in a children's hospital: the Antibiotic Mapping of Prescribing (ABMAP) study

BACKGROUND

The World Health Organization has identified antimicrobial resistance (AMR) as one of the most significant global risks facing modern medicine. Interventions to improve antibiotic prescribing have so far had limited impact.

AIM

To understand the barriers to effective antibiotic prescribing.

METHODS

Mixed methodologies were used to investigate prescribing behaviours to identify the critical points in the antibiotic prescribing pathway for hospital inpatients. We assessed knowledge, experience or empowerment of prescribers, organizational factors, and use of the laboratory. Phase 1 was an online survey to map barriers and facilitators to antibiotic prescribing (56 participants). Phase 2 consisted of focus groups and interviews to gain more understanding of prescribing behaviours (10 participants). Phase 3 was an online survey to obtain opinions on possible solutions (22 participants).

FINDINGS

Barriers to prescribing were: laboratory factors 71.6%, resource issues 40%, time constraints 17.5%, pressure from others 52%. Ninety-three percent of prescribers were concerned about AMR. In three scenarios only 9% were confident not to prescribe antibiotics for a patient without bacterial infection; 53% would prescribe unnecessarily broad-spectrum antibiotics for pneumonia. Only 5% would de-escalate antibiotics in a microbiologically confirmed bacteraemia. Despite concerns about AMR, prescribers did not perceive that continuing antibiotics for individual patients might promote resistance. Prescribers were unwilling to change antibiotics out of hours and reported that they preferred professional support for antibiotic prescribing.

CONCLUSION

There was a marked disparity between prescribers, self-reporting of prescribing behaviour and responses to clinical scenarios. It was not clear whether training alone would change behaviours. Prescribers desired a directive mechanism to support antibiotic prescribing and stewardship.

Two-Step Nanoscale Approach for Well-Defined Complex Alkanethiol Films on Au Surfaces

Controlling the molecular organization of organic self-assembled monolayers (SAM) is of utmost importance in nanotechnology, molecular electronics, and surface science. Here we propose two well-differentiated approaches, double printing based on microcontact printing (μ-cp) and molecular backfilling adsorption, to produce complex alkanethiol films. The resulting films on model Au surfaces were characterized by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Double printing alkanethiols results in clear coexisting regions where no molecular displacement is observed, highlighting the slow diffusion rates of long alkanethiols and large attractive interaction between long alkyl chains. Exposing a single-print μ-cp Au substrate to an additional alkanethiol solution yields the formation of differently ordered domain boundaries with different thickness and micrometer lateral size. The high order is a result of enhanced molecular mobility and restructuring during solution backfilling. The formed molecular assemblies constitute an excellent testing ground for nanoscale phenomena that strongly depend on the nanoscale geometrical and chemical features of the surface such as designed functionality or corrosion initiation and inhibition.

Evaluation of an Urdu version of the Impact of Event Scale - Revised

In the aftermath of the major earthquake that hit Pakistan in 2005, there appeared to be a paucity of psychometric tools validated in Urdu. It was decided to translate the Impact of Event Scale - Revised (IES-R) so as to obtain an internationally validated and recognised psychometric tool for use in research into post-traumatic stress disorder. The resulting Urdu and English versions of the IES-R were compared for linguistic, conceptual and scale equivalence. The Urdu version of the IES-R (UIES-R) can be used for clinical, psychological trauma populations in Pakistan with evidence of good reliability and satisfactory validity. In trauma research in Pakistan the UIES-R will be an extremely useful psychometric tool.

Analysis of Ge micro-cavities with in-plane tensile strains above 2

Ge on Si micro-disk, ring and racetrack cavities are fabricated and strained using silicon nitride stressor layers. Photoluminescence measurements demonstrate emission at wavelengths ≥ 2.3 μm, and the highest strained samples demonstrate in-plane, tensile strains of > 2 %, as measured by Raman spectroscopy. Strain analysis of the micro-disk structures demonstrate that shear strains are present in circular cavities, which can detrimentally effect the carrier concentration for direct band transitions. The advantages and disadvantages of each type of proposed cavity structure are discussed.

Cardiac autonomic dysfunction in young obese males is not associated with disturbances in pituitary-thyroid axis hormones

OBJECTIVE

Obesity has been associated with hypothyroidism and cardiac autonomic dysfunction. The present study aimed to investigate whether cardiac autonomic dysfunction in young obese males might be related to an underlying thyroid disturbance.

PATIENTS AND METHODS

On the basis of body mass index (BMI), 40 participants were grouped into normal weight group (NW; BMI = 18.5-25 kg/m(2); n = 15), over weight group (OW; BMI = 25-29.9 kg/m(2); n = 12) and obese group (OB; BMI ≥ 30 kg/m(2); n = 13). Electrocardiogram was recorded using PowerLab system and the time and frequency domain measures of heart rate variability (HRV) were calculated. Fasting blood samples were drawn for measurement of serum thyroid stimulating hormone (TSH), total thyroxin (TT4) and total triiodothyronine (TT3) concentrations.

RESULTS

The levels of TSH, TT4 and TT3 were not significantly different between the groups. The frequency domain HRV parameter reflecting parasympathetic tone (high-frequency normalized units, HFnu) was significantly reduced in OB group. The parameters which reflect sympathetic activation (Heart rate, low-frequency normalized units; LFnu and the LF/HF ratio) were significantly increased in the OB group. HFnu was significantly and negatively correlated with BMI, waist hip ratio and body fat percentage, whereas LFnu and LF/HF ratio were significantly and positively correlated with the above mentioned parameters. No significant relationships were noted between the HRV parameters and the levels of TSH or thyroid hormones.

CONCLUSIONS

Cardiac autonomic dysfunction in obese young adult males is not linked with underlying thyroid disturbance.

Localized dealloying corrosion mediated by self-assembled monolayers used as an inhibitor system

The structure and chemistry of thiol or selenol self-assembled organic monolayers have been frequently addressed due to the unique opportunities in functionalization of materials. Such organic films can also act as effective inhibition layers to mitigate oxidation or corrosion. Cu–Au alloy substrates covered by self-assembled monolayers show a different dealloying mechanism compared to bare surfaces. The organic surface layer inhibits dealloying of noble metal alloys by a suppression of surface diffusion at lower potentials but at higher applied potentials dealloying proceeds in localized regions due to passivity breakdown. We present an in situ atomic force microscopy study of a patterned thiol layer applied on Cu–Au alloy surfaces and further explore approaches to change the local composition of the surface layers by exchange of molecules. The pattern for the in situ experiment has been applied by micro-contact printing. This allows the study of corrosion protection with its dependence on different molecule densities at different sites. Low-density thiol areas surrounding the high-density patterns are completely protected and initiation of dealloying proceeds only along the areas with the lowest inhibitor concentration. Dealloying patterns are highly influenced and controlled by molecular thiol to selenol exchange and are also affected by introducing structural defects such as scratches or polishing defects.

Predatory potential of Platynectes sp. (Coleoptera: Dytiscidae) on Aedes albopictus, the vector of dengue/chikungunya in Kerala, India

Unused and discarded latex collection containers (LCCs) are the major breeding habitats of Aedes albopictus in the rubber plantations of Kerala, India. Platynectes sp. (Family: Dytiscidae) was observed to invade these habitats during the monsoon season and voraciously devour the larval instars of this major vector species of arbo-viral diseases. Field observations showed a reduction of 70.91% (p = 0.0017) and 100% in Aedes larval density, on the first and four days post release of eight beetles per LCC respectively. In laboratory, a beetle was found to devour 17.75 + 5.0 late larval instars of Ae. albopictus per day. Our findings indicate Platynectes sp. could be a potential bio-control agent against Ae. albopictus, the vector of chikungunya/dengue fevers, in rubber plantations.

Transmission of methicillin-resistant Staphylococcus aureus via deceased donor liver transplantation confirmed by whole genome sequencing

Donor-derived bacterial infection is a recognized complication of solid organ transplantation (SOT). The present report describes the clinical details and successful outcome in a liver transplant recipient despite transmission of methicillin-resistant Staphylococcus aureus (MRSA) from a deceased donor with MRSA endocarditis and bacteremia. We further describe whole genome sequencing (WGS) and complete de novo assembly of the donor and recipient MRSA isolate genomes, which confirms that both isolates are genetically 100% identical. We propose that similar application of WGS techniques to future investigations of donor bacterial transmission would strengthen the definition of proven bacterial transmission in SOT, particularly in the presence of highly clonal bacteria such as MRSA. WGS will further improve our understanding of the epidemiology of bacterial transmission in SOT and the risk of adverse patient outcomes when it occurs.

Delayed aorto-right atrial fistula following percutaneous closure of atrial septal defect

We present the case of a 27-year-old man who underwent percutaneous atrial septal defect (ASD) repair using the Amplatzer(®) (St Jude Medical, St Paul, MN, US) septal occluder (ASO). Six weeks later, he presented with heart failure and was found to have an aorto-right atrial fistulation. He required urgent surgical device explantation and repair of the existing ASD using a pericardial patch repair technique. This is the first case to be reported from the UK describing a delayed aorto-right atrial fistula following percutaneous closure using ASO.

The impact of age and chronic kidney disease on secondary prevention post-primary percutaneous coronary intervention

OBJECTIVE

Historical data suggest elderly patients and those with chronic kidney disease (CKD) receive suboptimal secondary prevention following myocardial infarction (MI). We evaluated the impact of age and CKD on secondary prevention following primary percutaneous coronary intervention (PPCI) in a contemporary unselected cohort.

DESIGN

We studied 1169 consecutive patients from five UK centres receiving PPCI for ST elevation MI, with use of evidence-based secondary prevention at discharge assessed by age (<60, 60-75 and >75 years) and estimated glomerular filtration rate (eGFR). Follow-up prescribing practice was assessed in 567 patients.

RESULTS

One-fifth of patients receiving PPCI were >75 years. This group received fewer secondary prevention drugs at discharge compared to younger patients (P < 0.01 for β-blockers, angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARB) and statins). By 6 weeks post-PPCI, there was a small drop-off in evidence-based therapy; β-blocker and statin use in those >75 years fell from 90% to 86% and 96% to 93%, respectively. CKD (eGFR<60 ml/min/1.73 m(2)) was seen in 17.6%. Declining renal function was associated with age, female sex and lower use of ACE inhibitor/ARB. At discharge 83.5% of patients with eGFR<60 ml/min/1.73 m(2) were receiving ACE inhibitors/ARB, dropping to 77.5% at 6 weeks (compared with 95% and 92%, respectively, in patients with eGFR >60 ml/min/1.73 m(2)).

CONCLUSION

The uptake of secondary prevention medication is high following PPCI in the UK, even in the elderly and in those with renal dysfunction. A focus on strategies to improve up-titration and continuation of drugs following discharge is required.

Active infection and morphometric study of Trypanosoma evansi among horses in Peninsula Malaysia

Apart from occasional reports of clinical disease affecting horses, there is no information about Trypanosoma evansi in horses in Peninsula Malaysia. Thus, a cross-sectional study was conducted in eight states in Peninsula Malaysia to determine the active presence of T. evansi in horses. A total of 527 blood samples were obtained and examined by haematocrit centrifugation technique (HCT), Giemsa-stained thin blood smear (GSS), morphometric measurements, polymerase chain reaction (PCR) and cloning of PCR products. The results showed an overall parasitological prevalence of 0.57% (3/527, CI: 1.6-0.19%) with both HCT and GSS. Morphometric study revealed the mean total length of the trypanosomes including the free flagellum was 27.94 ± 2.63 μm. PCR successfully amplified a trypanosome specific 257 bp in 1.14% of samples (6/527, CI: 2.4-0.52%) and was confirmed by nucleotide sequences. The mean packed cell volume (PCV) for the positive cases detected by HCT was lower (23% ± 7.00) compared to the positive cases detected by PCR alone in the state of Terengganu (35% ± 4.73). In conclusion, this study showed T. evansi infection occurred in low frequency in horses in Peninsula Malaysia, and anaemia coincided with parasitaemic animals. PCR is considered as a sensitive diagnostic tool when parasitaemia is undetectable. The slight lengthier mean of parasite and anaemia may indicate a virulent strain of T. evansi circulating throughout the country. Thus, it's highly recommended to shed light on host-parasite relationship for better epidemiological understanding.

Metabolic responses of acute phase protein, antioxidant and cytokine in Arabian Endurance horses

Changes in serum amyloid A (SAA), glutathione reductase (GR) and interleukin-6 (IL-6) could be responsible for the metabolic disorders and poor performance in Arabian horses during gruelling endurance events. Therefore, this study aims to evaluate the metabolic responses in relation to SAA, GR and IL-6 in Arabian horses during endurance events. After physical examination, the successfully completed (SC) (n=16) and eliminated-from-race (ER) (n=16) endurance horses were identified. The data obtained were analysed using ANOVA and pairwise correlations and the analysis were considered significant at P<0.05. There were significant differences between the SC and ER Arabian horses in haemoglobin (Hb), packed cell volume (PCV), creatine kinase, plasma protein, lactate and monocytes (P<0.0001), IL-6, GR (P<0.0007), SAA (P<0.0068), glucose (P<0.00342), aspartate transaminase (P<0.0049) concentrations. There were significant negative correlations between GR and plasma protein (r=-0.2830; P<0.0299) and GR and SAA (r=-0.2554; P<0.0489). There were significant positive correlations between IL-6 and Hb (r=0.2977; P<0.0220) and positive and not significant correlation between IL-6 and PCV (r=0.2449; P<0.0615). In conclusion, SAA, GR and IL-6 were significantly associated with metabolic crises in Arabian endurance horses. Therefore, SAA, GR and IL-6 could be used to evaluate performance and health status of endurance horses during training and endurance events.

GLOMERULAR FILTRATION RATE PROFILES IN PAEDIATRIC PATIENTS ON CANCER CHEMOTHERAPY AT THE KENYATTA NATIONAL HOSPITAL, KENYA

BACKGROUND

An accurate estimation of renal function in children is important in optimising the dose of many drugs used in paediatric oncology for allowing clinical monitoring of the nephrotoxic effects of cytotoxic agents such as cisplatin. The glomerular filtration rate (GFR) is widely accepted as the best index of renal function in patients. Chemotherapy is the mainstay of treatment in the paediatric oncology unit at the Kenyatta National Hospital.

OBJECTIVES

To determine the glomerular filtration rate profiles of paediatric oncology patients and to assess changes that had occured over a period of at least six months of continuing cancer chemotherapy.

DESIGN

Cross-sectional hospital based survey.

SETTING

General Paediatric wards, including Paediatric Oncology and Paediatric Ophthalmology ward. Kenyatta National Hospital, Nairobi, Kenya. Subjects: Paediatric patients who had an established diagnosis of cancer and had been on chemotherapy for at least six months.

RESULTS

Out of the 115 children enrolledin the study 43 had abnormal kidney function, This gave a prevalence of 37% (95% CI 28-46).The other 72 children had normal kidney function. Patients aged less than five years and those with solid tumors had a higher likelihood of having an abnormal GFR compared to their older counterparts and thosc with-lymphomas and leukemias.

CONCLUSIONS

Monitoring of GFR should be done regularly as decline occurs as one continues on chemotherapy especially for the ones below five years and those witl solid malignancies.

Effect of psychosine on inducible nitric-oxide synthase expression under different culture conditions: implications for Krabbe disease

BACKGROUND AND OBJECTIVES

Krabbe disease is a neuro-inflammatory disorder in which galactosyl sphingosine (psychosine) accumulates in nervous tissues. Despite some leads in elucidating the mechanism of psychosine action on different cells of brain, there still remain gaps in the knowledge and mechanisms behind events in the pathogenic cascade of Krabbe disease. Inflammation in the brain in Krabbe disorder is an important factor in neural damage. This study was undertaken to access the role of psychosine in the regulation of nitric oxide (NO) and inducible nitric oxide synthase (iNOS), i.e., inflammatory markers, under two different conditions viz., using a single cell line and using primary mixed glial cells.

MATERIALS AND METHODS

BV2 murine microglial cells and murine primary mixed glial cells were used during this study. The cell lines, after 12 hr serum starvation, were treated with lipopolysaccharide (LPS) at 25 ng/ml in the absence or presence of increasing concentrations of psychosine (5, 10 and 15 microM). Formation of NO was estimated using Greiss reagent, and expression of iNOS was done by SDS-page followed by western blotting using anti-iNOS antibody.

RESULTS

In BV2 cells it was found that LPS (25 ng/ml) treatment, induced production of NO, but the LPS induced NO production was inhibited when LPS was used in combination with psychosine. This result was corroborated by parallel trend seen in iNOS expression under same conditions. Contrary to this, LPS (25 ng/ml) induced production of NO in primary mixed glial cells was dose dependently enhanced when LPS was used in combination with psychosine (5, 10 and 15 microM). This result was also corroborated by iNOS expression under same experimental conditions.

DISCUSSION

This study suggests that in-vitro data obtained using individual cell lines may not reflect the actual complex intricacies involved in development of Krabbe brain pathology. And that the effect of psychosine in Krabbe brain may be modulated by presence of LPS or other pro-inflammatory stimuli in the brain of these children, e.g., after an infection.

Anger arousal and well being as markers of social functioning and quality of life in the aftermath of exposure to life threatening trauma

Introduction

Severe stress or exposure to life threatening trauma is known to affect social functioning and quality of life.

Objectives

To study well-being and anger arousal as markers of social functioning and quality of life in a group of University students exposed to a suicide bomb attack on a University in Pakistan.

Aims

To examine indicators of social functioning in order to higlight them as targets for therapeutic interventions.

Methods

Subjects were assessed after one year of exposure to a life threatening incident on University campus. Subjects completed an assessment schedule incorporating World Health Organization's Well-Being Index and Novarco Anger Inventory (25 items).

Results

54 students completed the assessment. The mean age of the group was 24 years. All subjects had completed 14–16 years of education and were in full time education at the time of assessment. The Well Being Index Score range was 1–24 with 26 sujects scoring 13 or lower scores indicating poor quality of life. 29 subjects scored higer levels of anger arousal on 10 or more items of Novarco Anger Inventory indicating difficulties in social functioning. The overall group showed a statistically significant negative correlation between the Well-Being Index Scores and the number of Novarco Anger Inventory items scored in the two highest categories of anger arousal.

Conclusions

The results of the study highlight anger arousal and well-being as important markers of functioning in the aftermath of a stressful life event. The study confirms their usefulness as legitimate therapeutic targets for pharmacotherapy, psychotherapeutic, and social interventions.

Concordance in Muslim patients in primary care

Focal points

Self-assembled monolayers of benzylmercaptan and para-cyanobenzylmercaptan on gold: surface infrared spectroscopic characterization

Self-assembled monolayers (SAMs) on gold substrates were prepared from benzylmercaptan (BM) and para-cyanobenzylmercaptan (pCBM), and the resulting surfaces were investigated using conventional infrared reflection-absorption spectroscopy (IRRAS) as well as polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS). IRRAS data are analyzed by comparison with transmission IR spectra and theoretical (DFT) simulations. The spectroscopic results indicate the presence of well-ordered monolayers of BM and pCBM with an orientation perpendicular to the surface. IRRAS and PM-IRRAS data are compared to each other and the respective merits of both methods are discussed.

Improved calibration technique for in vivo proton MRS thermometry for brain temperature measurement

The most common MR-based approach to noninvasively measure brain temperature relies on the linear relationship between the (1)H MR resonance frequency of tissue water and the tissue's temperature. Herein we provide the most accurate in vivo assessment existing thus far of such a relationship. It was derived by acquiring in vivo MR spectra from a rat brain using a high field (11.74 Tesla [T]) MRI scanner and a single-voxel MR spectroscopy technique based on a LASER pulse sequence. Data were analyzed using three different methods to estimate the (1)H resonance frequencies of water and the metabolites NAA, Cho, and Cr, which are used as temperature-independent internal (frequency) references. Standard modeling of frequency-domain data as composed of resonances characterized by Lorentzian line shapes gave the tightest resonance-frequency versus temperature correlation. An analysis of the uncertainty in temperature estimation has shown that the major limiting factor is an error in estimating the metabolite frequency. For example, for a metabolite resonance linewidth of 8 Hz, signal sampling rate of 2 Hz and SNR of 5, an accuracy of approximately 0.5 degrees C can be achieved at a magnetic field of 3T. For comparison, in the current study conducted at 11.74T, the temperature estimation error was approximately 0.1 degrees C.

Self-assembled monolayers of benzylmercaptan and p-cyanobenzylmercaptan on Au(111) surfaces: structural and spectroscopic characterization

The formation of self-assembled monolayers of benzylmercaptan (BM) and p-cyanobenzylmercaptan (pCBM) on Au(111) surfaces is investigated by a combination of X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS), and scanning tunneling microscopy (STM). The NEXAFS results of pCBM are supported by ab initio calculations. It is found that BM as well as pCBM form well-ordered monolayers with the molecules oriented almost perpendicular to the surface. BM forms a ( radical 3 x radical 3)R30 degrees structure whereas pCBM forms a slightly different c(7 x 7) hexagonal structure. No phase separation is detected for the adsorption of a 1:1 mixture of the two molecules. The implications of the results for the covalent attachment of transition-metal complexes to thiol-functionalized surfaces are discussed.

Antinociceptive and antipyretic activities of theZizyphus oxyphylla Edgew. leaves

A methanol extract of Zizyphus oxyphylla Edgew leaves has been investigated for its analgesic and antipyretic activities in Adult Wistar and Swiss albino mice of either sex at 50, 100 and 200 mg/kg orally. The extract demonstrated marked antipyretic activity against Brewer's yeast-induced pyrexia in rats. The extract demonstrated significant peripheral analgesic effect in the acetic acid-induced writhing test in mice. The phytochemical tests revealed that the extract contained alkaloids, anthraquinones, flavonoids, glycosides, phenols, resins, saponins and tannins using standard procedures. In conclusion, the present study suggests that the methanol extract of Zizyphus oxyphylla Edgew leaves possesses potent antipyretic and antinociceptive activities and thus validates its use in the treatment of pain and fever.

Combined STM and FTIR characterization of terphenylalkanethiol monolayers on Au(111): effect of alkyl chain length and deposition temperature

Self-assembled monolayers (SAMs) of 4,4'-terphenyl-substituted alkanethiols C6H5(C6H4)2(CH2)n-SH (TPn, n = 1-6) on Au (111) substrates were studied using scanning tunneling microscopy (STM) and infrared reflection absorption spectroscopy (IRRAS). When the SAMs were prepared at room temperature (RT, 298 K), TPn films (except TP2) exhibit an odd-even effect regarding both molecular orientation and packing density. For all investigated films, STM data reveals the presence of a large degree of lateral order. In the case of odd-numbered TPns, the films revealed a (2 square root(3) x square root(3))R30 degree molecular arrangement. For the even-numbered TP4 and TP6 SAMs, a c(5 square root(3) x 3) rectangular unit cell was found. The packing density for the even-numbered TPn SAMs is 25% lower than that for the odd-numbered TPn SAMs. When the SAMs were prepared at 333 K, the even-numbered SAMs were found to form structures with a significantly lower packing density. In the case of TP2, instead of the (2 square root(3) x square root(3))R30 degree structure formed at room temperature, a c(5 square root(3) x 3) structure was observed. For TP6 SAMs, the room-temperature c(5 square root(3) x 3) structure was replaced by a (6 square root(3) x 2 square root(3))R30 degree structure.

Electrochemically deposited Pd islands on an organic surface: the presence of Coulomb blockade in STM I(V) curves at room temperature

Palladium islands with a thickness of a few monolayers were deposited on top of a self-assembled monolayer (SAM) fabricated from 4-mercaptopyridine. In the I(V) curves obtained using the scanning tunneling microscope (STM) clearly the signature of Coulomb blockade is observed, explicitly demonstrating that these islands are coupled to the underlying gold substrate only via a tunneling barrier; this spectroscopic feature also allows to distinguish the palladium islands from similar morphological features present on the gold substrate prior to palladium deposition.

Changes in RANKL/OPG/RANK gene expression in peripheral mononuclear cells following treatment with estrogen or raloxifene

The RANKL/OPG/RANK pathway is the key mediator of osteoclastogenesis. Mononuclear cells may be implicated in post-menopausal osteoporosis. The effect of estrogen or raloxifene on bone resorption and the expression of RANKL/OPG/RANK in peripheral blood mononuclear cells (PBMCs) was examined. Twenty-nine women with post-menopausal osteoporosis were treated with estrogen (HRT) or raloxifene for 12 months. Bone mineral density (BMD) was measured at baseline and at 12 months at the spine and hip. Serum C-terminal telopeptide (CTX) and OPG were measured at baseline and at 1, 3, 6 and 12 months. PBMCs were isolated from 17 women and changes in RANKL, OPG and RANK mRNA were determined. The effects of estrogen or raloxifene in PBMCs in vitro were also assessed. BMD increased following treatment (lumbar spine % change mean [S.E.M.]: 4.3% [0.9], p<0.001). Serum CTX decreased (6 months: -43.7% [6.0], p<0.0001). Serum OPG declined gradually (12 months: -26.4% [4.4], p<0.001). RANKL, OPG and RANK gene expression decreased (6 months: RANKL 50.0% [24.8] p<0.001, OPG: 21.7% [28] p<0.001, RANK: 76.6% [10.2] p=0.015). Changes in OPG mRNA correlated with changes in BMD (r=-0.53, p=0.027) and CTX (r=0.7, p=0.0044). Down-regulation in RANKL, OPG, RANK mRNA and reduction in bone resorption was also seen in vitro. These results suggest that the expression of RANKL/OPG/RANK in PBMCs are responsive to the slowing in bone turnover/remodeling associated with treatment with estrogen or raloxifene. Further confirmatory studies are needed.

Mild intellectual disability in children in Lahore, Pakistan: aetiology and risk factors

BACKGROUND

One of the main objectives of studying intellectual disability (ID) in children is to explore its causes. A specific aetiological diagnosis is important in determining the prognosis, nature and extent of services needed to support affected children.

METHODS

Aetiology and risk factors in mild ID were studied in a cohort of longitudinally followed children (6-10 years of age, n = 40) in four population groups in and around Lahore, Pakistan.

RESULTS

The overall prevalence of mild ID was 6.2%. In 22% of the cases the onset of mild ID was prenatal with small for gestational age and multifactorial inheritance as the main underlying factors. During the postnatal period (28% of the cases), social deprivation and malnutrition were the major causes of ID. In a substantial proportion of the cases (50%), the cause of ID could not be traced.

CONCLUSION

The present study indicates a clear relationship of mild ID with prenatal and postnatal malnutrition and social deprivation. Two independent variables, maternal illiteracy and small head circumference at birth, showed a clear association with the development of mild mental disability among children in the study population.

Transgenic tobacco expressing geminiviral RNAs are resistant to the serious viral pathogen causing cotton leaf curl disease

Cotton, the major cash crop in Pakistan, suffers 30% losses to cotton leaf curl disease, caused by the geminivirus, cotton leaf curl virus DNA A, plus a satellite component, DNA beta responsible for symptom development with plants failing to produce cotton bolls. We constructed transgenic tobacco expressing sense and antisense RNAs representing: [i] the 5' half of the viral DNA replication gene, AC1, [ii] the 3' half of AC1, [iii] two overlapping genes, AC2, a transcription activator, and AC3, a replication enhancer. In contrast to controls, 25% of 72 transgenic tobacco lines tested showed heritable resistance [T(1) - T(3) generations]: symptom-free and no replication of DNA A or DNA beta even after 120 days of continuous exposure to viruliferous whiteflies. As geminiviral and transgene RNAs are not detected in resistant lines following infection, and selected uninfected resistant tobacco sense lines reveal double-stranded and small interfering RNAs, the most likely mechanism is via post-transcriptional gene silencing.

The effect of special training for quinacrine sterilization (QS) in Faisalabad, Pakistan: a report on an 1833-women subset of 11,000 cases

OBJECTIVE

To determine the impact of retrained clinicians on the efficacy of transcervical quinacrine sterilization.

METHOD

Retraining of clinicians in the accepted insertion technique was conducted in 1996. From 1 January 1997 through 2001, they performed 1089 quinacrine sterilizations in 11 MCH clinics of the Mother & Child Welfare Association at Faisalabad, Pakistan. Of these, 885 women had a recorded follow-up visit (81.4%) by 31 December 2001.

RESULT

Reported pregnancy failures declined after retraining from 5.4% (SE 2.3) for one year of use to 1.1% (SE 0.4) for 5 years of use. The rates at 4 years of use showed the expected increase in failures for women 30 years old or younger of 1.5% (SE 0.7) compared to 0.9% (SE 0.4) for those over 30; a lower rate of 0.8% (SE 0.4) for breastfeeding subjects and 2.2% (SE 1.1) for mothers not breastfeeding; but rates were similar for uterine length and post insertion traumatic bleeding.

CONCLUSION

Quinacrine sterilization appears safe with acceptable efficacy.

Cotton leaf curl disease is associated with multiple monopartite begomoviruses supported by single DNA beta

For bipartite begomoviruses (family Geminiviridae) trans-replication of the DNA B component by the DNA A-encoded replication-associated protein (Rep) is achieved by virtue of a shared sequence, the "common region", which contains repeated motifs (iterons) which are sequence-specific Rep binding sites and form part of the origin of replication. Recently cotton leaf curl disease (CLCuD), a major constraint to cotton production on the Indian subcontinent, has been shown to be caused by a monopartite begomovirus ( Cotton leaf curl Multan virus [CLCuMV]) and a novel single-stranded DNA satellite molecule termed CLCuD DNA beta. The satellite molecule is trans-replicated by CLCuMV but does not possess the iteron sequences of this virus. We have investigated the ability of CLCuD DNA beta to interact with three further clones of monopartite begomoviruses, isolated from cotton, that have distinct Rep binding specificities. All three cloned viruses were capable of trans-replicating the satellite molecule and inducing CLCuD symptoms in cotton, indicating that the interaction between begomovirus and DNA beta is relaxed in comparison to the interaction between DNA A and DNA B components. Field surveys across all the cotton growing regions of Pakistan indicate that dual and multiple infections are the norm for CLCuD with no evidence of synergism. Despite the diversity of begomoviruses associated with CLCuD, only a single class of DNA beta has been detected, suggesting that this satellite has the capacity to be recruited by unrelated begomoviruses.