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.

Atrial Appendage Aneurysms: Natural History and Outcomes

BACKGROUND

Left (LAAA) and right atrial appendage aneurysms (RAAA) are rare entities, and their natural history, management, and long-term outcomes are not well studied.

METHODS

This retrospective review includes all patients from 2000 to 2021 with atrial appendage aneurysms at our institution identified using an electronic search tool. LAAA and RAAA were confirmed using multimodality imaging and intraoperative findings.

RESULTS

We identified 13 (87%) patients with LAAA and 2 (13%) with RAAA. At diagnosis, 11 (73%) were female, mean age was 51.4  ±  18.8 years, and ejection fraction 56.5  ±  13.1%. Three (20%) patients had congenital heart disease including 2 (13%) with atrioventricular septal defects and 1 (7%) with congenitally corrected transposition. LAAA/RAAA was diagnosed due to new-onset atrial fibrillation (AF) in 6 (40%) patients and embolic stroke in 2 (13%). Ten patients had preexisting AF diagnosed 2.9  ±  1.4 years earlier at a mean age of 50.2  ±  15.5 years. Thrombus within the aneurysm was identified in 2 (15%) LAAA patients. All patients were on anticoagulation and follow-up of the cohort from diagnosis was 7.1  ±  6.2 years. Eleven (73%) patients were surgically managed with 7 (64%) lesions excised, 1 (9%) stapled, and 3 (27%) ligated. Postoperative complications occurred in 2 (18%) patients with 1 (7%) developing tricuspid regurgitation and another with pericardial effusion and tamponade.

CONCLUSIONS

Atrial appendage aneurysm is a rare disease and nearly half of patients present with AF. Surgical treatment with concomitant AF ablation is a reasonable and safe management option.

Predicting Permanent Pacemaker Implantation following Trans-catheter Aortic Valve Replacement: A Contemporary Meta-Analysis of 981,168 patients

Background

Heart block requiring permanent pacemaker (PPM) implantation is a relatively frequent complication of transcatheter aortic valve replacement (TAVR).

Objective

The purpose of this study was to perform a contemporary meta-analysis to provide an updated assessment of clinically useful predictors of PPM implantation post-TAVR.

Methods

Medline and EMBASE searches were performed to include all studies reporting PPM post-TAVR between 2015 and 2020. Pertinent data were extracted from the studies for further analysis. RevMan was used to create forest plots and calculate risk ratios (RRs).

Results

We evaluated 41 variables from 239 studies with a total of 981,168 patients. From this cohort, 17.4% received a PPM following TAVR. Strong predictors for PPM implant were right bundle branch block (RBBB) (RR 3.12; P <.001) and bifascicular block (RR 2.40; P = .002). Intermediate factors were chronic kidney disease (CKD) (RR 1.53; P <.0001) and first-degree atrioventricular block (FDAVB) (RR 1.44; P <.001). Weak factors (RR 1–1.50; P <.05) were male gender, age ≥80 years, body mass index ≥25, diabetes mellitus (DM), atrial fibrillation (AF), and left anterior fascicular block (LAFB). These factors along with increased left ventricular outflow tract (LVOT) area (>435 mm²) and/or aortic annulus diameter (>24.4 mm) were incorporated to propose a new scoring system to stratify patients into high- and low-risk groups.

Conclusion

Male gender, age ≥80 years, FDAVB, RBBB, AF, DM, CKD, Medtronic CoreValve, transfemoral TAVR, increased LVOT, and aortic annulus diameter were significant predictors of post-TAVR PPM implantation. Preprocedural assessment should consider these factors to guide clinical decision-making before TAVR. Validation of our scoring system is warranted.

Identification of phytochemical inhibitors of SARS-CoV-2 protease 3CLpro from selected medicinal plants as per molecular docking, bond energies and amino acid binding energies

Recent worldwide outbreak of SARS-COV-2 pandemic has increased the thirst to discover and introduce antiviral drugs to combat it. The bioactive compounds from plant sources, especially terpenoid have protease inhibition activities so these may be much effective for the control of viral epidemics and may reduce the burden on health care system worldwide. Present study aims the use of terpenoid from selected plant source through bioinformatics tools for the inhibition of SARS-COV-2. This study is based on descriptive analysis. The Protein Data Bank and PubChem database were used for the analysis of SARS-COV-2 protease and plant source terpenoids. Molecular docking by using molegro virtual docker (MVD) software was carried out. The findings of study are based on the inhibitory actions of different plant sourced terpenoid against SARS-COV-2. As per the available resources and complementary analysis these phytochemicals have capacity to inhibit 3CL^pro protease. The study reports that (3,3-dimethylally) isoflavone (Glycine max), licoleafol (Glycyrrhiza uralensis), myricitrin (Myrica cerifera), thymoquinone (Nigella sativa), bilobalide, ginkgolide A (Ginkgo biloba), Salvinorin A (Salvia divinorum), citral (Backhousia citriodora) and prephenazine (drug) showed high activity against SARS-COV-2 protease 3CL^pro. The drug like and ADMET properties revealed that these compounds can safely be used as drugs. Cross structural analysis by using bioinformatics study concludes that these plant source terpenoid compounds can be effectively used as antiprotease drugs for SARS-COV-2 in future.

Safety and Efficacy Outcomes of Atrial Fibrillation Ablation in Patients with Rheumatoid Arthritis

Background

Rheumatoid arthritis (RA) is an immune-mediated inflammatory disease associated with atrial fibrillation (AF) and stroke.

Objective

The purpose of this study was to evaluate the safety and efficacy of AF ablation in patients with RA.

Methods

All patients with RA undergoing AF ablation at our institution from 2010 to 2021 were propensity matched to patients without RA using 9 baseline characteristics. The primary outcome was procedural efficacy defined by clinical AF recurrence, the need for antiarrhythmic drugs (AADs), and repeat catheter ablation. Secondary outcome was safety.

Results

A total of 45 patients with RA (age 66.3 ± 7.7 years) were matched to 45 patients without a history of RA (age 68.0 ± 7.3 years). Both groups had similar procedural and periprocedural characteristics. Before ablation, RA patients had statistically higher C-reactive protein (CRP) levels (P ≤.01) and erythrocyte sedimentation rates (ESRs) (P <.05) compared to non-RA patients. After ablation, RA patients had statistically significant higher rates of AF recurrence (P = .006), were more likely to be taking AADs (P <.05), and more likely to undergo repeat ablations (P <.05). The use of immunosuppression or corticosteroids at the time of ablation did not influence the primary endpoint of AF recurrence, AADs, or repeat ablation. Multivariate regression analysis showed CRP and ESR were independent predictors of AF recurrence. CRP was an independent predictor of repeat ablation.

Conclusion

Patients with RA are at higher risk of clinical AF recurrence, and are more likely to be taking AADs and require repeat ablation. Preablation CRP and ESR are independent predictors of AF recurrence, and CRP is an independent predictor of repeat catheter ablation.

Phosphorylated and O-GlcNAc Modified IRS-1 (Ser1101) and -2 (Ser1149) Contribute to Human Diabetes Type II

BACKGROUND

The prevalence of the chronic metabolic disorder Type 2 diabetes mellitus (T2DM) is increasing steadily, and has even turned into an epidemic in some countries. T2DM results from defective responses to insulin and obesity is a major factor behind insulin resistance in T2DM. Insulin receptor substrate (IRS) proteins are adaptor proteins in the insulin receptor signalling pathway. The insulin signalling is controlled through tyrosine phosphorylation of IRS-1 and IRS-2, and dysregulation of IRS proteins signalling may lead to glucose intolerance and eventually insulin resistance.

OBJECTIVE

In this work, we suggest that both glycosylation (O-GlcNAc modification) and phosphorylation of IRS-1 and -2 are involved in the pathogenesis of T2DM.

METHODS

Phosphorylation and O-GlcNAc modifications (Ser1101 in IRS-1 and Ser1149 in IRS-2) proteins were determined experimentally by sandwich ELISA with specific antibodies and with bioinformatics tools.

RESULTS

When IRS-1 (on Ser1101) and IRS-2 (Ser1149) become glycosylated following an increase in UDP-GlcNAc pools, it may contribute to insulin resistance. Whereas when the same (IRS-1 on Ser1101 and IRS-2 on Ser1149) are phosphorylated, the insulin signalling is inhibited.

DISCUSSION

In this work OGlcNAc-modified proteins were specifically detected using O-Glc- NAc-specific antibodies, suggesting that elevated levels of O-GlcNAc-modified proteins are found, independently of their possible involvement in Advanced Glycation End products (AGEs).

CONCLUSION

This study suggests a mechanism, which is controlled by posttranslational modifications, and may contribute to the pathogenesis of type II diabetes.

Artificial intelligence in personalized cardiovascular medicine and cardiovascular imaging

The collection of large, heterogeneous electronic datasets and imaging from patients with cardiovascular disease (CVD) has lent itself to the use of sophisticated analysis using artificial intelligence (AI). AI techniques such as machine learning (ML) are able to identify relationships between data points by linking input to output variables using a combination of different functions, such as neural networks. In cardiovascular medicine, this is especially pertinent for classification, diagnosis, risk prediction and treatment guidance. Common cardiovascular data sources from patients include genomic data, cardiovascular imaging, wearable sensors and electronic health records (EHR). Leveraging AI in analysing such data points: (I) for clinicians: more accurate and streamlined image interpretation and diagnosis; (II) for health systems: improved workflow and reductions in medical errors; (III) for patients: promoting health with further education and promoting primary and secondary cardiovascular health prevention. This review addresses the need for AI in cardiovascular medicine by reviewing recent literature in different cardiovascular imaging modalities: electrocardiography, echocardiography, cardiac computed tomography, cardiac nuclear imaging, and cardiac magnetic resonance (CMR) imaging as well as the role of EHR. This review aims to conceptulise these studies in relation to their clinical applications, potential limitations and future opportunities and directions.

Imaging to evaluate suspected infective endocarditis

Although echocardiography is fundamental in diagnosing infective endocarditis, sometimes it reveals no evidence of endocarditis while clinical indicators remain consistent with the diagnosis. In such cases, repeat imaging is necessary, and the appropriate timeline for it and whether it should be done with transthoracic echocardiography (TTE), trans esophageal echocardiography (TEE), or an advanced imaging method are important.

Resistance mechanisms and population structure of highly drug resistant Klebsiella in Pakistan during the introduction of the carbapenemase NDM-1

Klebsiella pneumoniae is a major threat to public health with the emergence of isolates resistant to most, if not all, useful antibiotics. We present an in-depth analysis of 178 extended-spectrum beta-lactamase (ESBL)-producing K. pneumoniae collected from patients resident in a region of Pakistan, during the period 2010–2012, when the now globally-distributed carbapenemase bla-NDM-1 was being acquired by Klebsiella. We observed two dominant lineages, but neither the overall resistance profile nor virulence-associated factors, explain their evolutionary success. Phenotypic analysis of resistance shows few differences between the acquisition of resistance genes and the phenotypic resistance profile, including beta-lactam antibiotics that were used to treat ESBL-positive strains. Resistance against these drugs could be explained by inhibitor-resistant beta-lactamase enzymes, carbapenemases or ampC type beta-lactamases, at least one of which was detected in most, but not all relevant strains analysed. Complete genomes for six selected strains are reported, these provide detailed insights into the mobile elements present in these isolates during the initial spread of NDM-1. The unexplained success of some lineages within this pool of highly resistant strains, and the discontinuity between phenotypic resistance and genotype at the macro level, indicate that intrinsic mechanisms contribute to competitive advantage and/or resistance.

Ten-year single-centre experience with type II endoleaks: Intervention versus observation

Our objective was to determine the relative merits of intervention or observation of type II endoleaks (T2Ls). A retrospective analysis was performed on 386 infra-renal endovascular aneurysm repair (IR-EVAR) patients from 2006 to 2015. Annual surveillance imaging of patients undergoing EVAR at our centre were analysed, and all endoleaks were subjected to a multidisciplinary team meeting for consideration and treatment. In the 10-year time frame, 386 patients (79.5±8.7 years) underwent an IR-EVAR. Eighty-one patients (21.0%) developed a T2L and intervention was undertaken in 28 (34.6%): 17 (60.7%) were treated via a transarterial approach (TA) and 11 (39.3%) using the translumbar approach (TL). Fifty-three patients (65.4%) with T2Ls were managed conservatively. Patients who received T2L treatment had a greater proportion of recurrent T2Ls than patients who were conservatively managed ( p=0.032). T2Ls associated with aneurysmal growth were more resistant to treatment than those where there was no change or a decrease in aneurysm size during follow-up (0.033). There was no significant difference in the TA and TL approach with respect to endoleak repair success ( p=0.525). Treatment of a T2L did not confer a survival advantage compared to conservative management ( p=0.449) nor did the choice of either the TA or TL approach ( p=0.148). Our study suggests the development of a T2L associated with aneurysm growth may represent an aggressive phenotype that is resistant to treatment. However, this did not lead to an increased risk of mortality over follow-up. Neither a transarterial nor a translumbar approach to treating a T2L conferred superiority.

Bronchodilator activity of aerial parts of Polygonatum verticillatum augmented by anti-inflammatory activity: attenuation of Ca²⁺ channels and lipoxygenase

Polygonatum verticillatum is commonly used for the treatment of asthma and inflammation. The current study was aimed to scrutinize the pharmacological profile of methanolic extract of the aerial parts (PA). Isolated tracheal preparations were used for the evaluation of bronchodilatory activity, whilst the in vivo carrageenan-induced paw oedema test and an in vitro lipoxygenase (LOX) inhibitory assay were used for the assessment of the anti-inflammatory profile of PA. When tested against carbachol and K⁺ (80 mM)-induced contractions, PA caused complete inhibition of isolated rabbit tracheal preparations in a dose-dependent mode, similar to verapamil. While elucidating possible mechanism, PA shifted the Ca²⁺ concentration-response curves to the right, analogous to that produced by verapamil, confirming a Ca²⁺ channel blocker-like activity. PA provoked profound reduction in paw oedema with a maximum protection of 60.87% at 200 mg/kg i.p. in a dose-dependent manner which was augmented by its prominent LOX inhibitory activity (IC₅₀ : 125 µg/mL). These findings authenticated its therapeutic potential in the treatment of asthmatic and inflammatory conditions.

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.

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.

Influence of dissolved oxygen concentration on intracellular pH for regulation of Aspergillus niger growth rate during citric acid fermentation in a stirred tank bioreactor

In this paper we report the regulation of Aspergillus niger growth rate during citric acid fermentation in a stirred tank bioreactor. For this, the influence of dissolved oxygen concentration in a medium on intracellular pH values and consequently on overall microbial metabolism was emphasized. Intracellular pH of mycelium grown under different concentrations of dissolved oxygen in the medium was determined. Sensitivity of proteins toward proton concentration is well recognized, therefore pH influences on the activities of key regulatory enzymes of Aspergillus niger were determined at pH values similar to those detected in the cells grown under lower dissolved oxygen concentrations. The results have shown significantly reduced specific activities of hexokinase, 6-phosphofructokinase and glucose-6-phosphate dehydrogenase in more acidic environment, while pyruvate kinase was found to be relatively insensitive towards higher proton concentration. As expected, due to the reduced specific activities of regulatory enzymes under more acidic conditions, overall metabolism should be hindered in the medium with lower dissolved oxygen concentration which was confirmed by detecting the reduced specific growth rates. From the studies, we conclude that dissolved oxygen concentration affects the intracellular pH and thus growth rate of Aspergillus niger during the fermentation process.

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.

Stimulatory effect of alcohols (methanol and ethanol) on citric acid productivity by a 2-deoxy D-glucose resistant culture of aspergillus niger GCB-47

The present study describes citric acid fermentation by Aspergillus niger GCB-47 in a 15-1 stainless steel stirred fermentor. Among the alcohols tested as stimulating agents, 1.0% (v/v) methanol was found to give maximum amount of anhydrous citric acid (90.02 +/- 2.2 g/l), 24 h after inoculation. This yield of citric acid was 1.96 fold higher than the control. Methanol has a direct effect on mycelial morphology and it promotes pellet formation. It also increases the cell membrane permeability to provoke more citric acid excretion from the mycelial cells. The sugar consumed and % citric acid was 108 +/- 3.8 g/l and 80.39 +/- 4.5%, respectively. The desirable mycelial morphology was in the form of small round pellets having dry cell mass 14.5 +/- 0.8 g/l. Addition of ethanol, however, did not found to enhance citric acid production, significantly. The maximum value of Yp/x (i.e., 5.825 +/- 0.25 g/g) was observed when methanol was used as a stimulating agent. The best results of anhydrous citric acid were observed, 6 days after inoculation when the initial pH of fermentation medium was kept at 6.0.

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.

Sheffield risk and treatment table for cholesterol lowering for primary prevention of coronary heart disease

When used for the secondary prevention of coronary heart disease, treatment with an inhibitor of hydroxymethylglutaryl-coenzyme-A reductase results in worthwhile benefit that clearly exceeds any risk in patients whose risk of coronary death is 1.5% or more per year. This evidence can be extrapolated logically to primary prevention of coronary disease provided that treatment is targeted at those with similar or higher risk. We present a table that refines previously proposed methods of risk prediction. The table identifies subjects who have the specified degree of coronary risk; shows the serum cholesterol concentration that confers that degree or risk in the individual; and identifies subjects who will not have this degree of risk, irrespective of their cholesterol concentration. It is simple enough for use in ordinary practice. The table highlights the predominant effect of age on coronary risk; a person who is free of vascular disease and younger than 52 years is unlikely to have the specified degree of risk. Even in older people (60-70 years) several risk factors are generally required to attain this degree of risk. Some people are candidates for lipid- lowering drug treatment with serum cholesterol as low as 5.5 mmol/L, whereas others with cholesterol as high as 9.0 mmol/L are not. Although cholesterol lowering is a powerful method for preventing coronary events in people at high risk, cholesterol measurement by itself is not a good way to identify those with high coronary risk. The method can be adapted readily to target a different level of coronary risk as new evidence on the benefit and risk of treatment becomes available.

Might non-pharmacological treatment disadvantage patients with hypertension?

Weight reduction, moderate salt restriction and alcohol reduction are effective in lowering blood pressure (BP), and are feasible interventions for long-term management of hypertension. When used in combination these non-pharmacological measures are significantly inferior to drug therapy in anti-hypertensive effect. When they are implemented as a first step in the treatment of mild hypertension, resorting to drug therapy only if non-pharmacological measures fail, anti-hypertensive drugs can be avoided in about 40% of patients. However, BP control is again significantly inferior with this strategy compared with drug therapy without non-pharmacological advice. Those given advice on non-pharmacological measures may therefore have suboptimal protection against cardiovascular complications. This is particularly so when the threshold for drug treatment is set at a DBP of > or = 100 mmHg, as many patients will be left untreated with DBPs between 90 and 99 mm Hg as a result of non-pharmacological measures. Non-pharmacological treatment may thus stand between patients and anti-hypertensive drug therapy, which nowadays is simple, well-tolerated, safe and proven effective in preventing cardiovascular disease. The role of non-pharmacological therapy needs to be reconsidered.