In Vitro Methods for the Investigation of sRNA-mRNA Interactions in Bacillus subtilis

So far, in Bacillus subtilis, only four trans-encoded and 11 cis-encoded sRNAs and their targets have been investigated in detail, the majority of them in our group (rev. in 1, 2). Here, we describe in vitro methods for the analysis of sRNA/mRNA interactions. All these methods have been either elaborated or significantly improved in our group and successfully applied to characterize a number of sRNA/target mRNA systems in Bacillus subtilis for which we provide examples from our own work. The in vitro methods comprise the synthesis and purification of labeled and unlabeled RNA, the analysis of sRNA/mRNA interactions in electrophoretic mobility shift assays (EMSAs) including the calculation of their apparent binding rate constants (kapp) and equilibrium dissociation constants (Kd), the localization of minimal regulatory regions of an sRNA, the determination of the secondary structures of both interacting RNAs and their complex as well as the analysis of RNA chaperones that may promote the sRNA/mRNA interaction.

Investigation of sRNA-mRNA Interactions in Bacillus subtilis In Vivo

In this chapter, we describe in vivo methods for the analysis of interactions between an sRNA and its target mRNA in B. subtilis. All these methods have been either established or significantly improved in our group and successfully employed to characterize a number of sRNA/target mRNA systems in Bacillus subtilis. Whereas in Chap. 8, we describe a combination of in vitro methods, e.g., EMSA and RNA secondary structure probing, we focus here on the investigation of RNA-RNA interactions in vivo using compatible plasmids or chromosomal insertions and deletions, the elucidation of the mechanisms of action of regulatory sRNAs employing transcriptional and translational reporter gene fusions, as well as the determination of expression profiles, half-lives of sRNA and mRNA, and their intracellular concentrations, and, finally, the investigation of RNA chaperones that promote the sRNA/mRNA interaction. For an in-depth analysis of sRNA-mRNA interactions in B. subtilis, a combination of in vivo and in vitro methods should be applied.

A comprehensive study of the interactions in the B. subtilis degradosome with special emphasis on the role of the small proteins SR1P and SR7P

Here, we employ coelution experiments and far-western blotting to identify stable interactions between the main components of the B. subtilis degradosome and the small proteins SR1P and SR7P. Our data indicate that B. subtilis has a degradosome comprising at least RNases Y and PnpA, enolase, phosphofructokinase, glycerol-3-phosphate dehydrogenase GapA, and helicase CshA that can be co-purified without cross-linking. All interactions were corroborated by far-western blotting with proteins purified from E. coli. Previously, we discovered that stress-induced SR7P binds enolase to enhance its interaction with and activity of enolase-bound RNase Y (RnY), while SR1P transcribed under gluconeogenic conditions interacts with GapA to stimulate its interaction with and the activity of RnjA (RnjA). We show that SR1P can directly bind RnjA, RnY, and PnpA independently of GapA, whereas SR7P only interacts with enolase. Northern blotting suggests that the degradation of individual RNAs in B. subtilis under gluconeogenic or stress conditions depends on either RnjA or RnY alone or on RnjA-SR1P, RnY-SR1P, or RnY-Eno. In vitro degradation assays with RnY or RnjA substrates corroborate the in vivo role of SR1P. Currently, it is unknown which substrate property is decisive for the utilization of one of the complexes.

Morphometric analysis and roosting ecology of bat species Pteropus Medius in Mansehra, Khyber Pakhtunkhwa, Pakistan

Morphometric measurement and roosting ecology of Pteropus medius were aimed to find out in Mansehra district of KP, Pakistan. Total 3149 numbers of bats were found in eight biological spots visited; Baffa Doraha, Darband, Dadar, Jallu, Hazara University, Garhi Habibullah Chattar Plain and Jabori, in total 299 numbers of different species of trees including; Morus alba, Pinus raxburghi, Eucalyptus camaldulensis, Morus nigra, Grevillea robusta, Brousonetia papyrifera, Platanus orientalis, Ailanthus altissima, Hevea brasiliensis and Populus nigra. Morphometric features were measured and found vary according to sex of the bats. The average wing span, wing`s length from tip of wing to neck, from thumb to tip of wing and the body`s length from head and claws were recorded to be 102.98 cm, 49.07cm, 28.7 cm and 22.78 cm respectively in males while 93.67 cm, 44.83cm, 24.78cm and 22.78 cm respectively in female bats. Mean circumference of the body including wings and without wing were measured as 22.78 cm and 17.29 cm in males and that of female were 20.07 cm and 16.9 cm. Average length of thumb 3.64 cm, ear`s length 3.1 cm, snout 5.62cm, eye length were 1.07 cm for both sexes and length between the feet in extended position were16.3 cm. Generally different measurement of males bodies were found to be greater than female such as mean body surface area, mass, volume and pressure were found to be 2691.79 cm2, 855.7gm,1236.4 ml and 295.77 dyne/ c m 3 for male and 2576.46 cm2, 852.71gm,1207 ml and 290.2 dyne/ c m 3 respectively for female. While weight and density for both males and females bats were same with mean of 8.59 newton and 0.701 g/m3. Findings of current reports can add valued information in literature about bats, which can be used for species identification and conservation.

How employees leverage psychological capital and perform, even in the presence of rude co-workers: an empirical study from Pakistan

Purpose

This study aims to unpack the link between co-worker incivility and job performance, by detailing a mediating role of psychological detachment and a moderating role of psychological capital.

Design/methodology/approach

The research hypotheses are tested with three-wave, time-lagged data collected from Pakistani-based employees and their supervisors.

Findings

An important reason that disrespectful co-worker treatment curtails job performance, with respect to both in-role and extra-role work efforts, is that employees detach from their work environment. This mediating role of psychological detachment is less salient to the extent that employees possess high levels of psychological capital.

Practical implications

For organizations, this study pinpoints a key mechanism, a propensity to distance oneself from work, by which convictions that co-workers do not show respect direct employees away from productive work activities. This study also shows how this mechanism can be subdued by ensuring that employees exhibit energy-enhancing personal resources.

Originality/value

This study expands extant research on the dark side of interpersonal co-worker relationships by revealing pertinent factors that explain why and when co-worker incivility can escalate into diminished performance-enhancing activities.

A new role for SR1 from Bacillus subtilis: regulation of sporulation by inhibition of kinA translation

SR1 is a dual-function sRNA from Bacillus subtilis. It inhibits translation initiation of ahrC mRNA encoding the transcription activator of the arginine catabolic operons. Base-pairing is promoted by the RNA chaperone CsrA, which induces a slight structural change in the ahrC mRNA to facilitate SR1 binding. Additionally, SR1 encodes the small protein SR1P that interacts with glyceraldehyde-3P dehydrogenase A to promote binding to RNase J1 and enhancing J1 activity. Here, we describe a new target of SR1, kinA mRNA encoding the major histidine kinase of the sporulation phosphorelay. SR1 and kinA mRNA share 7 complementary regions. Base-pairing between SR1 and kinA mRNA decreases kinA translation without affecting kinA mRNA stability and represses transcription of the KinA/Spo0A downstream targets spoIIE, spoIIGA and cotA. The initial interaction between SR1 and kinA mRNA occurs 10 nt downstream of the kinA start codon and is decisive for inhibition. The sr1 encoded peptide SR1P is dispensable for kinA regulation. Deletion of sr1 accelerates sporulation resulting in low quality spores with reduced stress resistance and altered coat protein composition which can be compensated by sr1 overexpression. Neither CsrA nor Hfq influence sporulation or spore properties.

Suffering doubly: How victims of coworker incivility risk poor performance ratings by responding with organizational deviance, unless they leverage ingratiation skills

Building on conservation of resources theory, this study investigates the relationship between employees' exposure to coworker incivility and their job performance ratings, while also considering the mediating role of their deviant work behaviors and the moderating role of their ingratiation skills. Results based on multisource, three-wave data from employees and their supervisors in Pakistani organizations show that disrespectful coworker treatment diminishes employees' performance evaluations, because they seek purposefully to cause harm to their employing organization, as a way to vent their frustrations. This mediating role of organizational deviance is mitigated to the extent that employees have a greater ability to ingratiate with others though. This study accordingly identifies a key mechanism - deviant work behaviors that undermine organizational well-being - through which coworker incivility leads to negative performance consequences, and it reveals how organizations can subdue this process by honing pertinent personal resources within their ranks.

Intermolecular Communication in Bacillus subtilis: RNA-RNA, RNA-Protein and Small Protein-Protein Interactions

In bacterial cells we find a variety of interacting macromolecules, among them RNAs and proteins. Not only small regulatory RNAs (sRNAs), but also small proteins have been increasingly recognized as regulators of bacterial gene expression. An average bacterial genome encodes between 200 and 300 sRNAs, but an unknown number of small proteins. sRNAs can be cis- or trans-encoded. Whereas cis-encoded sRNAs interact only with their single completely complementary mRNA target transcribed from the opposite DNA strand, trans-encoded sRNAs are only partially complementary to their numerous mRNA targets, resulting in huge regulatory networks. In addition to sRNAs, uncharged tRNAs can interact with mRNAs in T-box attenuation mechanisms. For a number of sRNA-mRNA interactions, the stability of sRNAs or translatability of mRNAs, RNA chaperones are required. In Gram-negative bacteria, the well-studied abundant RNA-chaperone Hfq fulfils this role, and recently another chaperone, ProQ, has been discovered and analyzed in this respect. By contrast, evidence for RNA chaperones or their role in Gram-positive bacteria is still scarce, but CsrA might be such a candidate. Other RNA-protein interactions involve tmRNA/SmpB, 6S RNA/RNA polymerase, the dual-function aconitase and protein-bound transcriptional terminators and antiterminators. Furthermore, small proteins, often missed in genome annotations and long ignored as potential regulators, can interact with individual regulatory proteins, large protein complexes, RNA or the membrane. Here, we review recent advances on biological role and regulatory principles of the currently known sRNA-mRNA interactions, sRNA-protein interactions and small protein-protein interactions in the Gram-positive model organism Bacillus subtilis. We do not discuss RNases, ribosomal proteins, RNA helicases or riboswitches.

SR7 - a dual-function antisense RNA from Bacillus subtilis

Here, we describe SR7, a dual-function antisense RNA encoded on the Bacillus subtilis chromosome. This RNA was earlier described as SigB-dependent regulatory RNA S1136 and reported to reduce the amount of the small ribosomal subunit under ethanol stress. We found that the 5ʹ portion of SR7 encodes a small protein composed of 39 amino acids which we designated SR7P. It is translated from a 185 nt SigB-dependent mRNA under five different stress conditions and a longer SigB-independent RNA constitutively. About three-fold higher amounts of SR7P were detected in B. subtilis cells exposed to salt, ethanol, acid or heat stress. Co-elution experiments with SR7P_C-FLAG and Far-Western blotting demonstrated that SR7P interacts with the glycolytic enzyme enolase. Enolase is a scaffolding component of the B. subtilis degradosome where it interacts with RNase Y and phosphofructokinase PfkA. We found that SR7P increases the amount of RNase Y bound to enolase without affecting PfkA. RNA does not bridge the SR7P-enolase-RNase Y interaction. In vitro-degradation assays with the known RNase Y substrates yitJ and rpsO mRNA revealed enhanced enzymatic activity of enolase-bound RNase Y in the presence of SR7P. Northern blots showed a major effect of enolase and a minor effect of SR7P on the half-life of rpsO mRNA indicating a fine-tuning role of SR7P in RNA degradation.

Perceived contract violation and job satisfaction

Purpose

This paper aims to investigate how employees’ perceptions of psychological contract violation or sense of organizational betrayal, might diminish their job satisfaction, as well as how their access to two critical personal resources – emotion regulation skills and work-related self-efficacy – might buffer this negative relationship.

Design/methodology/approach

Two-wave survey data came from employees of Pakistani-based organizations.

Findings

Perceived contract violation reduces job satisfaction, but the effect is weaker at higher levels of emotion regulation skills and work-related self-efficacy.

Practical implications

For organizations, these results show that the frustrations that come with a sense of organizational betrayal can be contained more easily to the extent that their employees can draw from relevant personal resources.

Originality/value

This investigation provides a more complete understanding of when perceived contract violation will deplete employees’ emotional resources, in the form of feelings of happiness about their job situation. A sense of organizational betrayal is less likely to escalate into reduced job satisfaction when employees can control their negative emotions and feel confident about their work-related competencies.

When ethics create misfit: Combined effects of despotic leadership and Islamic work ethic on job performance, job satisfaction, and psychological well-being

This study applies social exchange and person-environment fit theories to predict that despotic leaders tend to hinder employee job performance, job satisfaction, and psychological well-being, whereas employees' own Islamic work ethic (IWE) enhances these outcomes. Also, IWE moderates the relationship of despotic leadership with the three outcomes, such that it heightens the negative impacts, because employees with a strong IWE find despotic leadership particularly troubling. A multi-source, two-wave, time-lagged study design, with a sample (303 paired responses) of employees working in various organisations, largely supports these predictions. Despotic leadership and IWE relate significantly to job performance, job satisfaction and psychological well-being in the predicted directions, except that there is no significant relationship between IWE and job satisfaction. A test of moderation shows that the negative relationships of despotic leadership with job outcomes are stronger when IWE is high. These findings have pertinent implications for theory, as well as for organisational practice.

Threatened but Involved: Key Conditions for Stimulating Employee Helping Behavior

This article examines the relationship between employees’ job involvement and helping behavior directed toward coworkers, as well as how this relationship might be augmented when employees encounter adversity, whether due to malicious leadership (abusive supervision) or threats to their physical integrity (workplace hazards, fear of terrorism). Drawing on a two-wave survey research design that collected data from employees and their supervisors in Pakistan, the results reveal that job involvement increases the likelihood that employees go out of their way to help their coworkers, and this relationship is strongest when they have to deal with the hardships of malicious leadership or threats to their physical safety. For organizations, these findings indicate that employees perceive their own allocation of positive work energy, derived from their job involvement, to helping behaviors that assist other members as particularly useful when they also experience significant adversity, inside or outside the workplace.

The Relationship between Workplace Incivility and Helping Behavior: Roles of Job Dissatisfaction and Political Skill

This article investigates the mediating role of job dissatisfaction in the relationship between employees' perceptions of workplace incivility and their helping behavior, as well as the buffering role of political skill in this process. Three-wave, time-lagged data collected from employees and their supervisors revealed that employees' exposure to workplace incivility diminished their helping behavior through their sense of job dissatisfaction. This mediating role of job dissatisfaction was less salient, however, to the extent that employees were equipped with political skill. For organizations, this study accordingly pinpoints a key mechanism-namely, unhappiness about their job situation-through which rude coworker treatment links to lower voluntary workplace behaviors among employees, and it reveals how this mechanism can be better contained in the presence of political skill.

Does Despotic Leadership Harm Employee Family Life: Exploring the Effects of Emotional Exhaustion and Anxiety

Research has not focused on the negative effects of despotic leadership on subordinates' life satisfaction and the interface between work and family. Drawing on the Conservation of Resources theory, this research investigates the mediating effect of emotional exhaustion through which despotic leadership transcends from the workplace to subordinates' personal lives, resulting in work-family conflict and decreased life satisfaction. The research also examines the moderating effect of subordinates' anxiety on the relationship of their perceptions of despotic leadership with work-family conflict and life satisfaction. Three waves of time-lagged data was collected from 224 book sellers who work in publishing houses. We used Hayes' PROCESS to test moderation and SEM to test mediation. The results of the study suggest that despotic leadership is related to work-family conflict via emotional exhaustion, but offer no support for its relationship with life satisfaction. As expected, when subordinates' anxiety increases, the positive relationship between a supervisor's despotism and his or her subordinates' work-family conflict and the negative relationship between despotic leadership and life satisfaction both strengthen. The results suggest that despotic leaders harm their subordinates' non-work lives, and these effects intensify when subordinates have high levels of anxiety. These findings have important implications for service organizations in mitigating the negative effects of despotic leadership by minimizing subordinates' anxiety through coping mechanisms and giving reward and incentives.

Efficacy Of Intravenous Lignocain Vs Sevoflurane In Prevention Of Coughing And Desaturation At Extubation In Children

BACKGROUND

Inadvertent coughing and desaturation are the most commonly faced and feared respiratory complications in post-anaesthesia period. The study was done to compare the efficacy of intravenous lignocaine versus sevoflurane in prevention of coughing and desaturation at extubation in children less than 6 years of age.

METHODS

This Randomized Control Trial was carried out from May 2013 to May 2016, at Combined Military Hospital Nowshera after obtaining approval from the hospital ethics committee (IREC-0003/5/13/Aneas). Children aged three months to six years undergoing surgical procedures requiring the placement of definitive airway were randomly assigned into two groups. Patients were anaesthetized by standardized balanced anaesthesia technique. In Group A (n=355), three minutes prior to extubation lignocaine 2% was used intravenously. In Group B (n=355), isoflurane was switched off, breathing circuit changed and sevoflurane started at minimum alveolar concentration (MAC 3-4%) for 3 minutes prior to extubation. Assessment for extubation was clinical. Oxygen saturation and severity of coughing were noted for 5 consecutive minutes, after extubation.

RESULTS

In group-A, 156 patients were less than 2 years of age while in group-B, 135 patients were less than 2 years old. In group-A, 199 and in group-B, 220 children were 2-6 years of age respectively. Post stratification the p-value for weight was 0.17 (p-value >0.05) and t-statistic was 1.36. Post stratification p-value for gender was 0.12 (p-value>0.05) and chi square statistic was 2.49. Group A had more eventful extubation with 270 cases of cough (76%) as compared to group-B where it was noted in 199 cases (56%). Similarly, desaturation was observed in 85 cases in group-A (24%) as compared to 28 cases (8%) in group-B. The difference between the groups was statistically significant.

CONCLUSIONS

Sevoflurane based anaesthetic vapours mixture causes statistical significant prevention from events like coughing episodes and desaturation in post-extubation in children less than six years of age undergoing elective surgery.

QT interval prolongation in hospitalized patients on cardiology wards: a prospective observational study

PURPOSE

Prolonged QT interval may lead to a lethal form of arrhythmia, torsades de pointes (TdP), which is associated with cardiovascular mortality. Therefore, we aimed to identify prevalence of QT interval prolongation, compare clinical characteristics of patients with normal and prolonged QT interval, and identify predictors of QT interval prolongation.

METHODS

A prospective observational study was conducted in cardiology wards of two teaching hospitals in Pakistan. Bazett's correction formula was used for the calculation of QTc interval. Prevalence of QT prolongation and pro-QTc scores were calculated. Comparative analysis was performed with respect to various clinical characteristics by applying t test and chi-square test. Odds ratios were calculated using regression analysis.

RESULTS

Among 417 patients, 44.6% were found having prolonged QT interval, of which, 17.3% presented with an abnormally high QTc interval (> 500 ms). Significant difference was recorded between the groups (normal vs. prolonged) with respect to age, all prescribed medications, QT drugs, number of risk factors, QT-DDIs (QT-prolonging drug-drug interactions), gender, and diuretics use. Multivariate logistic regression analysis showed significant results for various predictors such as male gender (p = 0.03), various age categories 41-50 years (p = 0.04), 51-60 years (p = 0.01), and > 60 years (p < 0.001), and diuretics (p = 0.008).

CONCLUSION

A substantial number of patients in cardiology wards presented with QT prolongation. Proper considerations are needed in order to minimize the associated risk particularly in patients with abnormally high QT prolongation, old age, polypharmacy, one or more QT-prolonging drugs, and high pro-QTc scores.

Provenance based data integrity checking and verification in cloud environments

Cloud computing is a recent tendency in IT that moves computing and data away from desktop and hand-held devices into large scale processing hubs and data centers respectively. It has been proposed as an effective solution for data outsourcing and on demand computing to control the rising cost of IT setups and management in enterprises. However, with Cloud platforms user’s data is moved into remotely located storages such that users lose control over their data. This unique feature of the Cloud is facing many security and privacy challenges which need to be clearly understood and resolved. One of the important concerns that needs to be addressed is to provide the proof of data integrity, i.e., correctness of the user’s data stored in the Cloud storage. The data in Clouds is physically not accessible to the users. Therefore, a mechanism is required where users can check if the integrity of their valuable data is maintained or compromised. For this purpose some methods are proposed like mirroring, checksumming and using third party auditors amongst others. However, these methods use extra storage space by maintaining multiple copies of data or the presence of a third party verifier is required. In this paper, we address the problem of proving data integrity in Cloud computing by proposing a scheme through which users are able to check the integrity of their data stored in Clouds. In addition, users can track the violation of data integrity if occurred. For this purpose, we utilize a relatively new concept in the Cloud computing called “Data Provenance”. Our scheme is capable to reduce the need of any third party services, additional hardware support and the replication of data items on client side for integrity checking.

Serological Evidence of Scrub Typhus among Cases of PUO in the Kashmir Valley- A Hospital Based Study

INTRODUCTION

Rickettsial infections are being increasingly recognized as a cause of acute febrile illnesses and should be considered a distinct possibility in patients presenting with suggestive clinical features. Their diagnosis remains a challenge in a country like ours where tests like immunofluorescence assay cannot be routinely done. Results of serological tests, when correlated with patients clinical profile can aid in the timely diagnosis of scrub typhus.

AIM

To find out the extent to which scrub typhus contributes to Pyrexia of Unknown Origin (PUO) in patients admitted to or attending the OPD of our hospital using simple tests like Weil-Felix Agglutination Test (WFT) and Enzyme Linked Immunosorbent Assay (ELISA).

MATERIALS AND METHODS

A cross-sectional study was carried out in the Department of Microbiology, Government Medical College and Hospital, Srinagar, over a period of eight months (1(st) March to 31(st) October 2015). Serum samples from patients suffering from Pyrexia of Unknown Origin (PUO) were processed for the detection of Scrub typhus. A total of 162 samples were included in the study. These were subjected to WFT using OX-K strain. The serum samples were diluted 1/20 to 1/640 and a titre of ≥ 1:160 was considered as positive. The samples were also tested for IgM and IgG antibodies for scrub typhus by ELISA and tube agglutination test was done to detect typhoid fever and brucellosis.

RESULTS

Of the 162 serum samples tested 22.8% tested positive scrub typhus by WFT. IgM ELISA and IgG was positive in 8 (4.9%) and 15 (9.3%) samples respectively. Sensitivity, specificity, positive and negative predictive values of WFT; taking IgM ELISA as a reference standard were 75%, 79.9%, 16.2% and 98.4% respectively.

CONCLUSION

Scrub typhus is prevalent in our state and the results of WFT supplemented by those of ELISA can aid in its diagnosis. However the results of these tests should always be regarded in light of the clinical condition of the patient.

Formative research and development of an evidence-based communication strategy: the introduction of Vi typhoid fever vaccine among school-aged children in Karachi, Pakistan

The authors conducted formative research (a) to identify stakeholders' concerns related to typhoid fever and the need for disease information and (b) to develop a communication strategy to inform stakeholders and address their concerns and motivate for support of a school-based vaccination program in Pakistan. Data were collected during interactive and semi-structured focus group discussions and interviews, followed by a qualitative analysis and multidisciplinary consultative process to identify an effective social mobilization strategy comprised of relevant media channels and messages. The authors conducted 14 focus group discussions with the parents of school-aged children and their teachers, and 13 individual interviews with school, religious, and political leaders. Parents thought that typhoid fever was a dangerous disease, but were unsure of their children's risk. They were interested in vaccination and were comfortable with a school-based vaccination if conducted under the supervision of trained and qualified staff. Teachers and leaders needed information on typhoid fever, the vaccine, procedures, and sponsors of the vaccination program. Meetings were considered the best form of information dissemination, followed by printed materials and mass media. This study shows how qualitative research findings can be translated into an effective social mobilization and communication approach. The findings of the research indicated the importance of increasing awareness of typhoid fever and the benefits of vaccination against the disease. Identification and dissemination of relevant, community-based disease and vaccination information will increase demand and use of vaccination.

Mood and motor effects of thalamic deep brain stimulation surgery for essential tremor

PURPOSE

The aim of this study was to evaluate the effects of unilateral and bilateral ventralis intermedius (Vim) deep brain stimulation (DBS) on mood and motor function.

METHODS

Thirty-one consecutive medication refractory patients with essential tremor who underwent unilateral or bilateral Vim DBS at University of Florida and returned for at least 6 -month follow-up completed the Visual Analog Mood (VAMS), the Beck Depression Inventory (BDI), and the Tremor Rating Scale (TRS) before and after surgery. We excluded all patients who were implanted at other institutions.

RESULTS

The tense subscale of the VAMS improved significantly in both the unilateral and bilateral DBS groups (P < 0.001). On the VAMS afraid subscale, only the bilateral group trended toward improvement (P = 0.075). There were no significant changes for either group for the happy, confused, sad, angry, energetic or tired VAMS scores. TRS subscale scores all improved after unilateral and bilateral Vim DBS surgery (P < 0.001).

CONCLUSIONS

Feelings of tenseness, tremor severity and ADLs improved following unilateral or bilateral Vim DBS for ET.

Brain penetration effects of microelectrodes and DBS leads in STN or GPi

OBJECTIVE

To determine how intraoperative microelectrode recordings (MER) and intraoperative lead placement acutely influence tremor, rigidity, and bradykinesia. Secondarily, to evaluate whether the longevity of the MER and lead placement effects were influenced by target location (subthalamic nucleus (STN) or globus pallidus interna (GPi)).

BACKGROUND

Currently most groups who perform deep brain stimulation (DBS) for Parkinson disease (PD) use MER, as well as macrostimulation (test stimulation), to refine DBS lead position. Following MER and/or test stimulation, however, there may be a resultant "collision/implantation" or "microlesion" effect, thought to result from disruption of cells and/or fibres within the penetrated region. These effects have not been carefully quantified.

METHODS

47 consecutive patients with PD undergoing unilateral DBS for PD (STN or GPi DBS) were evaluated. Motor function was measured at six time points with a modified motor Unified Parkinson Disease Rating Scale (UPDRS): (1) preoperatively, (2) immediately after MER, (3) immediately after lead implantation/collision, (4) 4 months following surgery-off medications, on DBS (12 h medication washout), (5) 6 months postoperatively-off medication and off DBS (12 h washout) and (6) 6 months-on medication and off DBS (12 h washout).

RESULTS

Significant improvements in motor scores (p<0.05) (tremor, rigidity, bradykinesia) were observed as a result of MER and lead placement. The improvements were similar in magnitude to what was observed at 4 and 6 months post-DBS following programming and medication optimisation. When washed out (medications and DBS) for 12 h, UPDRS motor scores were still improved compared with preoperative testing. There was a larger improvement in STN compared with GPi following MER (p<0.05) and a trend for significance following lead placement (p<0.08) but long term outcome was similar.

CONCLUSION

This study demonstrated significant acute intraoperative penetration effects resulting from MER and lead placement/collision in PD. Clinicians rating patients in the operating suite should be aware of these effects, and should consider pre- and post-lead placement rating scales prior to activating DBS. The collision/implantation effects were greater intraoperatively with STN compared with GPi, and with greater disease duration there was a larger effect.

Choroidal metastasis from renal cell carcinoma presenting with cataract

We report a case of rare involvement of the eye with choroidal metastasis from renal cell carcinoma presenting 08 years after the primary tumor was removed. The patient initially presented with cataract most probably induced by the tumor. After cataract extraction, tumor was detected when it induced vitreous involvement and retinal detachment. Enucleation was performed and an extraocular mass was also excised. Histopathology confirmed the diagnosis of metastasis from renal cell carcinoma in the ocular tumor, extraocular mass and the vitreous.

Serum hormonal, electrolytes and trace element profiles in the rutting and non-rutting one-humped male camel (Camelus dromedarius)

The camel is known to be a seasonal breeder and, in the male camel, the breeding activity maximizes during the rutting period (winter and spring seasons). During the non-rutting period (summer and autumn), however, the breeding activity almost ceases completely. Serum steroid hormonal, electrolytes and trace element profiles were studied in 16 adult male camels aged 5-9 years, slaughtered during the rutting (n=8) and non-rutting periods (n=8). Moreover, testicular and epididymal tissue contents of electrolytes and trace elements were also studied during these two periods. Serum levels of testosterone, progesterone and T(4):T(3) ratio were higher in the rutting animals when compared to the non-rutting ones, while the reverse was true for serum T(3), T(4) and corticosterone levels (p<0.01). Among minerals, serum levels of sodium, calcium, copper and zinc were higher, while those of potassium were lower, in the rutting than non-rutting camels. In the testicular tissue, the levels of sodium, calcium, copper and iron were higher in the rutting group, while magnesium was higher in non-rutting one. In the epididymis, the tissue levels of chloride, iron and zinc were higher in the rutting than non-rutting period. These results demonstrate a clear evidence of the distribution of steroid hormones, electrolytes and trace elements forming and maintaining a certain level at two different physiological states in camels.

Pakistan's maternal and child health policy: analysis, lessons and the way forward

An estimated 400,000 infant and 16,500 maternal deaths occur annually in Pakistan. These translate into an infant mortality rate and maternal mortality ratio that should be unacceptable to any state. Disease states including communicable diseases and reproductive health (RH) problems, which are largely preventable account for over 50% of the disease burden. The analysis of Pakistan's maternal and child health (MCH) and family planning (FP) policy covers the period 1990-2002, and focuses on macroeconomic influences, priority programs and gaps, adequacy of resources, equity and organizational aspects, and the process of policy formulation. The overall MCH/FP policy is well directed. MCH/FP has been a priority in all policies; resource allocation, although unacceptably low, has substantially increased during the last decade; and there is a progressive shift from MCH to the reproductive health (RH) agenda. Areas in need of improvement include greater use of evidence as a basis for policy; increased priority to nutrition programs, measures to reduce neonatal and perinatal mortality, provision of emergency obstetric care, availability of skilled birth attendants, and a clear policy on integrated management of childhood illnesses. Enhanced planning capacity, development of a balanced human resource, improved governance to reduce staff absenteeism and frequent transfers, and a greater role of the private sector in the provision of services are some organizational aspects that need the governments' consideration. There are several lessons to be learnt: (i) Ministries of Health need sustained stewardship and well-documented evidence to protect cuts in resource allocation; (ii) frequent policy announcement sends inappropriate signals to managers and weakens on-going implementation; (iii) MCH/FP policies unless informed by evidence and participation of interest groups are unlikely to address gaps in programs; (iv) distributional and equity objectives of MCH/FP be addressed while setting overall national goals; (v) institutional capacity is a vital ingredient in translating MCH/FP policies into effective services. The suggested strategic directions emphasize, among others, the need for a comprehensive MCH/FP framework; strengthened stewardship in ministry of health, cost-effective strategies to address the gaps identified and doubling of the public sector resource allocation to MCH/FP over the next 5 years. The ability to ensure delivery of quality health services remains the biggest challenge in the Pakistani health sector. Unless sound policies are backed by well-functioning programs they are likely to become a victim of poor implementation.

Elevated levels of plasma homocysteine in hypertensive patients with diabetes mellitus

BACKGROUND

Homocysteine generates oxygen radicals (superoxide anion and hydrogen peroxide) that are known to produce vasoconstriction. Hypertension is a common problem in individuals with diabetes mellitus. It is possible that hypertension in diabetic patients may be due to increased levels of plasma homocysteine. We investigated the plasma levels of homocysteine, factors involved in homocysteine metabolism (serum folic acid and vitamin B12) and lipid peroxidation product in the serum of diabetic patients with hypertension.

METHODS AND RESULTS

The studies were conducted in three groups: 1) healthy controls, and diabetic patients who were 2) normotensive and 3) hypertensive. Plasma homocysteine, serum malondialdehyde (a lipid peroxidation product), vitamin B12, and folic acid were measured in these patients. Plasma homocysteine and serum malondialdehyde levels were elevated in diabetic patients compared to the control group. Plasma levels of homocysteine and serum levels of malondialdehyde were higher in the hypertensive diabetic patients than in those who were normotensive. Levels of serum folate were lower in hypertensive diabetic patients compared to the normotensive group. Levels of serum vitamin B12 were similar in both the normotensive and hypertensive diabetic patients.

CONCLUSIONS

Levels of plasma homocysteine and serum malondialdehyde are elevated in hypertensive diabetic patients. Hyperhomocysteinemia may be involved in the induction and sustaining of hypertension in diabetic patients.

Effect of volume of culture medium on enhanced citric acid productivity by a mutant culture of Aspergillus niger in stirred fermentor

AIMS

The present study deals with the effect of volume of culture medium on enhanced citric acid productivity by a mutant culture of Aspergillus niger.

METHODS AND RESULTS

A laboratory scale stirred fermentor of 15-l capacity was employed for all microbial cultivations. Blackstrap molasses, a by-product of sugar industries is easily and abundantly available for its exploitation as a carbon source in fermentation processes. The parental culture of A. niger was improved by mutation using ultraviolet radiations and N-methyl N-nitro N-nitroso guanidine, i.e. mutagen MNNG. Six MUV and eight MNNG-treated mutant strains were isolated after extensive screening and optimization. Mutant strain of A. niger MNNG-2 showed enhanced citric productivity (87.60 g l-1) over the parental strain BTL-45 (19.53 g l-1) and other mutant derivatives (49.85 g l-1 citric acid in case of mutant MUV-5 and 76.82 g l-1 in case of mutant MNNG-7). The optimal sugar level was found to be 150 g l-1 (optimum volume of the medium, 60%) after 6 days of inoculation, which is economically significant. Specific productivity of the mutant culture MNNG-2 (qp = 0.057 g/g cells h-1) was several folds higher than other strains.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of the present study are of commercial level. All kinetic parameters including yield coefficients and volumetric rates revealed the hyper-producibility of citric acid by mutant MNNG-2 using blackstrap molasses as the basal medium in stirred fermentor.

Statins for primary prevention: at what coronary risk is safety assured?

AIMS

Increasingly HMG CoA reductase inhibitors (statins) are being used for primary prevention of vascular disease in patients with a raised cholesterol but at low absolute risk of coronary heart disease (CHD). This study uses clinical trial results to explore the limits of absolute safety for statin use in such patients.

METHODS

The major placebo controlled statin outcome trials were identified by automated and manual literature searches. Principal results including all cause mortality in placebo and intervention groups and baseline values of standard coronary risk factors were abstracted for each trial. For the trials identified the reduction in overall mortality with statin treatment for each study was regressed against the underlying CHD risk of the population recruited into that trial using a statistically robust method.

RESULTS

The regression line describing the relationship between mortality benefit and risk suggests that statin use could be associated with an increase in mortality of 1% in 10 years. This would be sufficiently large to negate statin's beneficial effect on CHD mortality in patients with a CHD event risk less than 13% over 10 years.

CONCLUSIONS

Absolute safety of statins has not been demonstrated for patients at low risk of CHD. Patients absolute risk of CHD should be calculated before starting statin treatment for primary prevention. Extensions of such treatment to low risk patients should await further evidence of safety.

Crosstalk between p38, Hsp25 and Akt in spinal motor neurons after sciatic nerve injury

The p38 stress-activated protein kinase pathway is involved in regulation of phosphorylation of Hsp25, which in turn regulates actin filament dynamic in non-neuronal cells. We report that p38, Hsp25 and Akt signaling pathways were specifically activated in spinal motor neurons after sciatic nerve axotomy. The activation of the p38 kinase was required for induction of Hsp25 expression. Furthermore, Hsp25 formed a complex with Akt, a member of PI-3 kinase pathway that prevents neuronal cell death. Together, our observations implicate Hsp25 as a central player in a complex system of signaling that may both promote regeneration of nerve fibers and prevent neuronal cell death in the injured spinal cord.

Population implications of lipid lowering for prevention of coronary heart disease: data from the 1995 Scottish health survey

OBJECTIVE

To determine the proportion of the population, firstly, with cholesterol >/= 5.0 mmol/l and, secondly, with any cholesterol concentration, who might benefit from statin treatment for the following: secondary prevention of coronary heart disease (CHD); primary prevention at CHD risk 30%, 20%, 15%, and 6% over 10 years; and primary prevention at projected CHD risk 20% over 10 years (CHD risk at age 60 years if actual age < 60 years).

SUBJECTS

Random stratified sample of 3963 subjects aged 35-64 years from the Scottish health survey 1995.

RESULTS

For secondary prevention 7.8% (95% confidence interval (CI) 6.9% to 8.6%) of the population with cholesterol >/= 5.0 mmol/l would benefit from statins. For primary prevention, the prevalence of people at CHD risk 30%, 20%, 15%, and 6% over 10 years is 1.5% (95% CI 1.2% to 1.9%), 5.4% (95% CI 4.7% to 6.1%), 9.7% (95% CI 8.8% to 10.6%), and 32.9% (95% CI 31.5% to 34.4%), respectively. At projected CHD risk 20% over 10 years, 12.4% (95% CI 11.4% to 13.5%) would be treated with statins. Removing the 5.0 mmol/l cholesterol threshold makes little difference to population prevalence at high CHD risk.

CONCLUSIONS

Statin treatment would be required for 7.8% of the population for secondary prevention. For primary prevention, among other factors, guidelines should take into account the number of patients needing treatment at different levels of CHD risk when choosing the CHD risk to target. The analysis supports a policy of targeting treatment at CHD risk 30% over 10 years as a minimum, as recommended in current British guidelines, with a move to treating at CHD risk 15% over 10 years as resources permit.

Is coronary risk an accurate surrogate for cardiovascular risk for treatment decisions in mild hypertension? A population validation

OBJECTIVE

To examine the relationship between coronary (CHD) and cardiovascular (CVD) risk in patients with uncomplicated mild hypertension and to determine the accuracy of using CHD risk > or = 15% over 10 years to identify for antihypertensive treatment those patients with CVD risk > or = 20% over 10 years as advised in recent British guidelines.

DESIGN

Comparison of decisions made using CHD risk > or = 15% over 10 years calculated by the Framingham risk function and estimated using a simple table with CVD risk > or = 20% over 10 years.

SETTING

British population.

SUBJECTS

People aged 35-64 years with uncomplicated mild systolic hypertension (SBP 140-159 mmHg, n = 624) from the 1995 Scottish Health Survey.

MAIN OUTCOME MEASURES

Relationship between CHD and CVD risk. Sensitivity, specificity, positive and negative predictive values (PPV and NPV).

RESULTS

CHD risk 15% over 10 years was equivalent to CVD risk 21% over 10 years. Exact CHD risk > or = 15% over 10 years had sensitivity 79%, specificity 98%, PPV 94% and NPV 93% in detecting CVD risk > or = 20% over 10 years. Use of the table to estimate CHD risk > or = 15% over 10 years gave sensitivity 88%, specificity 90%, PPV 76% and NPV 95%.

CONCLUSION

CHD risk appears acceptably accurate for targeting treatment in mild hypertension. The risk assessment table, which slightly overestimates CHD risk, was more sensitive in identifying patients with CVD risk > or = 20% over 10 years and may be preferable to using exact CHD risk. European guidelines which suggest targeting treatment for mild hypertension at CHD risk > or = 20% over 10 years are over-conservative compared with British guidelines.

Solitary fibrous tumour of the spinal cord

We report an intramedullary primary solitary fibrous tumour of the cervical spinal cord in a 33-year-old man. The tumour predominantly consisted of monomorphic spindle cells with a storiform pattern. MRI demonstrated an inhomogeneously enhancing cervical intramedullary tumour. The patient was well without recurrence 18 months after surgery.

Implication of recent trials with b-hydroxy-b-methylglutaryl coenzyme A reductase inhibitors for hypertension management

BACKGROUND

There is broad agreement that statin treatment should be targeted at absolute coronary heart disease (CHD) risk but no consensus on the level of risk to target. We have examined the implications of adopting three different treatment policies for the management of hypertensive patients in the UK using data from treated hypertensives aged 35-69 years included in the Health Survey for England (1993).

METHODS

We calculated the proportion of hypertensive patients with existing atherosclerotic cardiovascular disease requiring statin treatment for secondary prevention of CHD. For those without atherosclerotic cardiovascular disease (primary prevention), we estimated CHD risk from the Framingham equation and examined the proportion with CHD risk exceeding thresholds of 4.5, 3 and 1.5% per year.

RESULTS

Twenty-one percent of treated hypertensives would require statin treatment for secondary prevention of CHD. When the CHD event threshold for statin treatment was set at > or =4.5% per year [equivalent to a number needed to treat (NNT) in 5 years of 13] a further 0.6% of hypertensive patients were identified for treatment; at a threshold of 3.0% per year (NNT = 20) 5.5% of patients were identified for primary prevention; and at a threshold of 1.5% per year (NNT = 40) 28.5% of patients were identified for primary prevention.

CONCLUSIONS

Those needing secondary prevention are first priority for statins and 21% of hypertensive patients will require treatment Formulation of guidelines for primary prevention should take into account the NNT; the proportion of patients targeted for treatment; the cost-effectiveness and the total cost of treatment. Current British guidance will entail treating an additional 5.5% of hypertensive patients for primary prevention and therefore 27% of hypertensive patients.

Cost effectiveness of HMG-CoA reductase inhibitor (statin) treatment related to the risk of coronary heart disease and cost of drug treatment

OBJECTIVES

To estimate the cost effectiveness of statin treatment in preventing coronary heart disease (CHD) and to examine the effect of the CHD risk level targeted and the cost of statins on the cost effectiveness of treatment.

DESIGN

Cohort life table method using data from outcome trials.

MAIN OUTCOME MEASURES

The cost per life year gained for lifelong statin treatment at annual CHD event risks of 4.5% (secondary prevention) and 3.0%, 2.0%, and 1.5% (all primary prevention), with the cost of statins varied from pound 100 to pound 800 per year.

RESULTS

The costs per life year gained according to annual CHD event risk were: for 4.5%, pound 5100; 3.0%, pound 8200; 2.0%, pound 10 700; and 1.5%, pound 12 500. Reducing the cost of statins increases cost effectiveness, and narrows the difference in cost effectiveness across the range of CHD event risks.

CONCLUSIONS

At current prices statin treatment for secondary prevention, and for primary prevention at a CHD event risk 3.0% per year, is as cost effective as many treatments in wide use. Primary prevention at lower CHD event risks (< 3.0% per year) is less cost effective and unlikely to be affordable at current prices and levels of health service funding. As the cost of statins falls, primary prevention at lower risk levels becomes more cost effective. However, the large volume of treatment needed will remain a major problem.

Prediction of coronary risk for primary prevention of coronary heart disease: a comparison of methods

Most recent guidelines advise targeting of lipid lowering for primary prevention at those at high absolute coronary (CHD) risk. We compared the accuracy of five CHD risk assessment methods in identifying such patients: one based on total cholesterol > or = 6.5 mmol/l plus two risk factors, and four based on the Framingham risk function (the European Task Force chart and Sheffield table, both using total cholesterol and the New Zealand chart and modified Sheffield table, both using total: HDL cholesterol ratio) for predicting CHD event risk > or = 2% per year, calculated by an independent risk function, PROCAM, in 126 treated hypertensive men. Cholesterol threshold plus two risk factors had sensitivity 59% and specificity 63%, did not identify some very high-risk patients, and identified very low-risk patients. Framingham-based methods using total cholesterol alone had sensitivity 90-98% and specificity 37-43%, and identified high-risk patients well, but identified some patients at very low risk. Methods based on total: HDL cholesterol ratio had sensitivity 90-98% and specificity 60-63%, and did not identify incorrectly patients at very low CHD risk. Methods based on cholesterol threshold and counting of risk factors are too inaccurate for targeting drug therapy for primary prevention of CHD. Framingham-based methods should incorporate HDL-cholesterol as the total: HDL cholesterol ratio.

Is the Framingham risk function valid for northern European populations? A comparison of methods for estimating absolute coronary risk in high risk men

OBJECTIVE

To examine the validity of estimates of coronary heart disease (CHD) risk by the Framingham risk function, for European populations.

DESIGN

Comparison of CHD risk estimates for individuals derived from the Framingham, prospective cardiovascular Münster (PROCAM), Dundee, and British regional heart (BRHS) risk functions.

SETTING

Sheffield Hypertension Clinic. Patients-206 consecutive hypertensive men aged 35-75 years without preexisting vascular disease.

RESULTS

There was close agreement among the Framingham, PROCAM, and Dundee risk functions for average CHD risk. For individuals the best correlation was between Framingham and PROCAM, both of which use high density lipoprotein (HDL) cholesterol. When Framingham was used to target a CHD event rate > 3% per year, it identified men with mean CHD risk by PROCAM of 4.6% per year and all had CHD event risks > 1.5% per year. Men at lower risk by Framingham had a mean CHD risk by PROCAM of 1.5% per year, with 16% having a CHD event risk > 3.0% per year. BRHS risk function estimates of CHD risk were fourfold lower than those for the other three risk functions, but with moderate correlations, suggesting an important systematic error.

CONCLUSION

There is close agreement between the Framingham, PROCAM, and Dundee risk functions as regards average CHD risk, and moderate agreement for estimates within individuals. Taking PROCAM as the external standard, the Framingham function separates high and low CHD risk groups and is acceptably accurate for northern European populations, at least in men.