Adequacy of control of cardiovascular risk factors in ambulatory patients with type 2 diabetes attending diabetes out-patients clinic at a county hospital,Kenya

Background

Type 2 diabetes is associated with substantial cardiovascular morbidity and mortality arising from the high prevalence of cardiovascular risk factors such as hypertension, dyslipidaemia, obesity, poor glycaemic control and albuminuria. Adequacy of control of these risk factors determines the frequency and outcome of cardiovascular events in the patients. Current clinical practice guidelines emphasize primary prevention of cardiovascular disease in type 2 diabetes. There is scarce data from the developing countries, Kenya included, on clinical care of patients with type 2 diabetes in the regions that are far away from tertiary health facilities. So we determined the adequacy of control of the modifiable risk factors: glycaemic control, hypertension, dyslipidemia, obesity and albuminuria in the study patients from rural and peri-urban dwelling.

Methods

This was a cross-sectional study on 385 randomly selected ambulatory patients with type 2 diabetes without overt complications. They were on follow up for at least 6 months at the Out-patient diabetes clinic of Nyeri County Hospital, a public health facility located in the central region of Kenya.

Results

Females were 65.5%. The study subjects had a mean duration of diabetes of 9.4 years, IQR of 3.0–14 years. Their mean age was 63.3 years, IQR of 56-71 years.Only 20.3% of our subjects had simultaneous optimal control of the three (3) main cardiovascular risk factors of hypertension, high LDL-C and hyperglycaemia at the time of the study. The prevalence of cardiovascular risk factors were as follows: HbA1c above 7% was 60.5% (95% CI, 55.6–65.5), hypertension, 49.6% of whom 76.6% (95% CI, 72.5–80.8) were poorly controlled. High LDL-Cholesterol above 2.0 mmol/L was found in 77.1% (95% CI 73.0–81.3) and Albuminuria occurred in 32.7% (95% CI 27.8–37.4). The prevalence of the other habits with cardiovascular disease risk were: excess alcohol intake at 26.5% (95% CI 27.8–37.4) and cigarette-smoking at 23.6%.A modest 23.4% of the treated patients with hypertension attained target blood pressure of <140/90 mmHg. Out of a paltry 12.5% of the statin-treated patients and others not actively treated, only 22.9% had LDL-Cholesterol of target <2.0 mmol/L.There were no obvious socio-demographic and clinical determinants of poor glycaemic control. However, old age above 50 yrs., longer duration with diabetes above 5 yrs. and advanced stages of CKD were significantly associated with hypertension. Female gender and age, statin non-use and socio-economic factor of employment were the significant determinants of high levels of serum LDL-cholesterol.

Conclusion

The majority of the study patients attending this government-funded health facility had high prevalence of cardiovascular risk factors that were inadequately controlled. Therefore patients with type 2 diabetes should be risk-stratified by their age, duration of diabetes and cardiovascular risk factor loading. Consequently, composite risk factor reduction strategies are needed in management of these patients to achieve the desired targets safely. This would be achieved through innovative care systems and modes of delivery which would translate into maximum benefit of primary cardiovascular disease prevention in those at high risk. It is a desirable quality objective to have a higher proportion of the patients who access care benefiting maximally more than the numbers we are achieving now.

     

The incidence of Campylobacter spp. on processed turkey from processing plants in the midwestern United States

AIM: The primary aim of this study was to determine the incidence of Campylobacter spp. on turkey, presented for processing at participating production plants located in the midwest region of the United States. METHODS AND RESULTS: The two participating plants were visited on a monthly basis for a period of 1 year. Sampling of carcasses was carried out using a surface swab technique. Swabs were obtained from carcasses at two points on the production line - prechill and postchill. In addition, samples of chill water were also obtained for examination. Isolation and detection of Campylobacter was carried out using enrichment in Preston broth with recovery of the organism on blood free Campylobacter selective agar (CCDA). Isolates recovered were screened and identified using the API Campy identification system. The study found that 34.9% of all samples tested were positive for Campylobacter spp. The overall, contamination rates observed for both plants were relatively similar (39.2% for plant A and 30.6% for plant B). Differences were observed in the incidence of Campylobacter spp. on prechill vs postchill carcasses (i.e. 40.8% prechill vs 37.6% postchill for plant A and 41.8% prechill vs 19.8% postchill for plant B). Campylobacter species most often isolated included Camp. jejuni and Camp. coli. Other species recovered were Camp. fetus fetus, Camp. upsaliensis and Camp. lari. CONCLUSIONS: The incidence of Campylobacter spp. on processed poultry was relatively common. Factors such as the processing plant examined, season and the farms presenting birds for processing influenced the incidence of the pathogen. SIGNIFICANCE AND IMPACT OF THE STUDY: Differences were observed in the prevalence of Campylobacter spp. isolated from the two plants examined. The study suggests a seasonal prevalence of Campylobacter in the cooler months with processing conditions also influencing the overall occurrence of the organism. The incidence, isolation and detection of Campylobacter spp. from processed poultry are discussed.     

From reaction kinetics to dementia: A simple dimer model of Alzheimer’s disease etiology

Oligomers of the amyloid β-protein (Aβ) have been implicated in the pathogenesis of Alzheimer’s disease (AD) through their toxicity towards neurons. Understanding the process of oligomerization may contribute to the development of therapeutic agents, but this has been difficult due to the complexity of oligomerization and the metastability of the oligomers thus formed. To understand the kinetics of oligomer formation, and how that relates to the progression of AD, we developed models of the oligomerization process. Here, we use experimental data from cell viability assays and proxies for rate constants involved in monomer-dimer-trimer kinetics to develop a simple mathematical model linking Aβ assembly to oligomer-induced neuronal degeneration. This model recapitulates the rapid growth of disease incidence with age. It does so through incorporation of age-dependent changes in rates of Aβ monomer production and elimination. The model also describes clinical progression in genetic forms of AD (e.g., Down’s syndrome), changes in hippocampal volume, AD risk after traumatic brain injury, and spatial spreading of the disease due to foci in which Aβ production is elevated. Continued incorporation of clinical and basic science data into the current model will make it an increasingly relevant model system for doing theoretical calculations that are not feasible in biological systems. In addition, terms in the model that have particularly large effects are likely to be especially useful therapeutic targets.     

Randomised Controlled Double-Blind Non-Inferiority Trial of Two Antivenoms for Saw-Scaled or Carpet Viper (Echis ocellatus) Envenoming in Nigeria

Background

In West Africa, envenoming by saw-scaled or carpet vipers (Echis ocellatus) causes great morbidity and mortality, but there is a crisis in supply of effective and affordable antivenom (ISRCTN01257358).

Methods

In a randomised, double-blind, controlled, non-inferiority trial, “EchiTAb Plus-ICP” (ET-Plus) equine antivenom made by Instituto Clodomiro Picado was compared to “EchiTAb G” (ET-G) ovine antivenom made by MicroPharm, which is the standard of care in Nigeria and was developed from the original EchiTAb-Fab introduced in 1998. Both are caprylic acid purified whole IgG antivenoms. ET-G is monospecific for Echis ocellatus antivenom (initial dose 1 vial) and ET-Plus is polyspecific for E. ocellatus, Naja nigricollis and Bitis arietans (initial dose 3 vials). Both had been screened by pre-clinical and preliminary clinical dose-finding and safety studies. Patients who presented with incoagulable blood, indicative of systemic envenoming by E. ocellatus, were recruited in Kaltungo, north-eastern Nigeria. Those eligible and consenting were randomly allocated with equal probability to receive ET-Plus or ET-G. The primary outcome was permanent restoration of blood coagulability 6 hours after the start of treatment, assessed by a simple whole blood clotting test repeated 6, 12, 18, 24 and 48 hr after treatment. Secondary (safety) outcomes were the incidences of anaphylactic, pyrogenic and late serum sickness-type antivenom reactions.

Findings

Initial doses permanently restored blood coagulability at 6 hours in 161/194 (83.0%) of ET-Plus and 156/206 (75.7%) of ET-G treated patients (Relative Risk [RR] 1.10 one-sided 95% CI lower limit 1.01; P = 0.05). ET-Plus caused early reactions on more occasions than did ET-G [50/194 (25.8%) and 39/206 (18.9%) respectively RR (1.36 one-sided 95% CI 1.86 upper limit; P = 0.06). These reactions were classified as severe in 21 (10.8%) and 11 (5.3%) of patients, respectively.

Conclusion

At these doses, ET-Plus was slightly more effective but ET-G was slightly safer. Both are recommended for treating E. ocellatus envenoming in Nigeria.

Trial Registration

Current Controlled Trials ISRCTN01257358     

Revision of the Malagasy genus Trichoteleia Kieffer (Hymenoptera, Platygastroidea, Platygastridae)

The species of the genus Trichoteleia Kieffer (Hymenoptera: Platygastridae) are revised: 42 species are recognized, of which two were previously named and are redescribed: Trichoteleia afo Talamas, sp. n., Trichoteleia albidipes Kieffer, Trichoteleia bicolor Talamas, sp. n.; Trichoteleia bidentata Talamas sp. n.; Trichoteleia carinata Talamas, sp. n.; Trichoteleia cincta Talamas & Masner, sp. n.; Trichoteleia delilah Talamas, sp. n.; Trichoteleia eburata Talamas, sp. n.; Trichoteleia echinata Talamas, sp. n.; Trichoteleia fisheri Talamas & Masner, sp. n.; Trichoteleia funesta Talamas, sp. n.; Trichoteleia halterata Talamas & Masner, sp. n.; Trichoteleia hemlyae Talamas & Masner, sp. n.; Trichoteleia irwini Talamas & Masner, sp. n.; Trichoteleia janus Talamas, sp. n.; Trichoteleia jiro Talamas, sp. n.; T. ketrona Talamas, sp. n.; Trichoteleia levii Talamas & Johnson, sp. n.; Trichoteleia longiventris Talamas & Masner, sp. n.; Trichoteleia minima Talamas, sp. n.; Trichoteleia nify Talamas & Masner, sp. n.; Trichoteleia oculea Talamas, sp. n.; Trichoteleia orona Talamas & Masner, sp. n.; Trichoteleia parvipennis Talamas & Masner, sp. n.; Trichoteleia pauliani (Risbec); Trichoteleia picturata Talamas, sp. n.; Trichoteleia prima Talamas, sp. n.; Trichoteleia prolixa Talamas, sp. n.; Trichoteleia quazii Talamas, sp. n.; Trichoteleia ravaka Talamas, sp. n.; Trichoteleia rugifrons Talamas & Masner, sp. n.; Trichoteleia solocis Talamas, sp. n.; Trichoteleia sphaerica Talamas, sp. n.; Trichoteleia subtilis Talamas & Masner, sp. n.; Trichoteleia tahotra Talamas & Masner, sp. n.; Trichoteleia takariva Talamas, sp. n.; Trichoteleia tezitra Talamas, sp. n.; Trichoteleia tigris Talamas, sp. n.; Trichoteleia tonsa Talamas, sp. n.; Trichoteleia warreni Talamas & Masner, sp. n.; Trichoteleia xantrox Talamas, sp. n.; Trichoteleia zuparkoi Talamas & Masner, sp. n. A neotype is designated for Trichoteleia albidipes and a lectotype is designated for Trichoteleia pauliani.     

Parameter Identification in a Generalized Time-Harmonic Rayleigh Damping Model for Elastography

The identifiability of the two damping components of a Generalized Rayleigh Damping model is investigated through analysis of the continuum equilibrium equations as well as a simple spring-mass system. Generalized Rayleigh Damping provides a more diversified attenuation model than pure Viscoelasticity, with two parameters to describe attenuation effects and account for the complex damping behavior found in biological tissue. For heterogeneous Rayleigh Damped materials, there is no equivalent Viscoelastic system to describe the observed motions. For homogeneous systems, the inverse problem to determine the two Rayleigh Damping components is seen to be uniquely posed, in the sense that the inverse matrix for parameter identification is full rank, with certain conditions: when either multi-frequency data is available or when both shear and dilatational wave propagation is taken into account. For the multi-frequency case, the frequency dependency of the elastic parameters adds a level of complexity to the reconstruction problem that must be addressed for reasonable solutions. For the dilatational wave case, the accuracy of compressional wave measurement in fluid saturated soft tissues becomes an issue for qualitative parameter identification. These issues can be addressed with reasonable assumptions on the negligible damping levels of dilatational waves in soft tissue. In general, the parameters of a Generalized Rayleigh Damping model are identifiable for the elastography inverse problem, although with more complex conditions than the simpler Viscoelastic damping model. The value of this approach is the additional structural information provided by the Generalized Rayleigh Damping model, which can be linked to tissue composition as well as rheological interpretations.     

Heritability of Subcortical Volumetric Traits in Mesial Temporal Lobe Epilepsy

Objectives

We aimed to 1) determine if subcortical volume deficits are common to mesial temporal lobe epilepsy (MTLE) patients and their unaffected siblings 2) assess the suitability of subcortical volumetric traits as endophenotypes for MTLE.

Methods

MRI-based volume measurements of the hippocampus, amygdala, thalamus, caudate, putamen and pallidium were generated using an automated brain reconstruction method (FreeSurfer) for 101 unrelated ‘sporadic’ MTLE patients [70 with hippocampal sclerosis (MTLE+HS), 31 with MRI-negative TLE], 83 unaffected full siblings of patients and 86 healthy control subjects. Changes in the volume of subcortical structures in patients and their unaffected siblings were determined by comparison with healthy controls. Narrow sense heritability was estimated ipsilateral and contralateral to the side of seizure activity.

Results

MTLE+HS patients displayed significant volume deficits across the hippocampus, amygdala and thalamus ipsilaterally. In addition, volume loss was detected in the putamen bilaterally. These volume deficits were not present in the unaffected siblings of MTLE+HS patients. Ipsilaterally, the heritability estimates were dramatically reduced for the volume of the hippocampus, thalamus and putamen but remained in the expected range for the amygdala. MRI-negative TLE patients and their unaffected siblings showed no significant volume changes across the same structures and heritability estimates were comparable with calculations from a healthy population.

Conclusions

The findings indicate that volume deficits for many subcortical structures in ‘sporadic’ MTLE+HS are not heritable and likely related to acquired factors. Therefore, they do not represent suitable endophenotypes for MTLE+HS. The findings also support the view that, at a neuroanatomical level, MTLE+HS and MRI-negative TLE represent two distinct forms of MTLE.     

Biodegradable zinc oxide composite scaffolds promote osteochondral differentiation of mesenchymal stem cells

Osteoarthritis (OA) involves the degeneration of articular cartilage and subchondral bone. The capacity of articular cartilage to repair and regenerate is limited. A biodegradable, fibrous scaffold containing zinc oxide (ZnO) was fabricated and evaluated for osteochondral tissue engineering applications. ZnO has shown promise for a variety of biomedical applications but has had limited use in tissue engineering. Composite scaffolds consisted of ZnO nanoparticles embedded in slow degrading, polycaprolactone to allow for dissolution of zinc ions over time. Zinc has well-known insulin-mimetic properties and can be beneficial for cartilage and bone regeneration. Fibrous ZnO composite scaffolds, having varying concentrations of 1–10 wt.% ZnO, were fabricated using the electrospinning technique and evaluated for human mesenchymal stem cell (MSC) differentiation along chondrocyte and osteoblast lineages. Slow release of the zinc was observed for all ZnO composite scaffolds. MSC chondrogenic differentiation was promoted on low percentage ZnO composite scaffolds as indicated by the highest collagen type II production and expression of cartilage-specific genes, while osteogenic differentiation was promoted on high percentage ZnO composite scaffolds as indicated by the highest alkaline phosphatase activity, collagen production, and expression of bone-specific genes. This study demonstrates the feasibility of ZnO-containing composites as a potential scaffold for osteochondral tissue engineering.