Spectrum of heart diseases in children presenting to a paediatric cardiac echocardiography clinic in the Lake Zone of Tanzania: a 7 years overview.

BACKGROUND: Congenital heart diseases (CHD) are among the most common congenital malformations. It is estimated that the incidence of CHD is constant worldwide, but data are rare for most African countries including Tanzania. Even less data are available on the prevalence of acquired heart diseases (AHD) in African children. Rheumatic heart disease (RHD) is the leading cause of AHD and is remaining a public health concern in Sub-Saharan Africa affecting especially the younger population. Both, CHD and AHD contribute substantially to morbidity and mortality during infancy and childhood. METHODS: This hospital-based, retrospective review of the registry at the paediatric cardiac clinic of Bugando Medical Centre in the Lake Zone of Tanzania analysed the spectrum of heart diseases of paediatric patients during their first presentation by using simple descriptive statistics. RESULTS: Between September 2009 and August 2016, a total of 3982 patients received cardiac evaluation including echocardiography studies. 1830 (46.0%) pathologic findings were described, out of these 1371 (74.9%) patients had CHD, whereas 459 (25.1%) presented with AHD. 53.9% of the patients with CHD were female and the most common associated syndrome was Down syndrome in 12.8% of patients. In 807 patients (58.9%) diagnosis of CHD was established within the first year of life. The majority of patients (60.1%) were in need of surgical or interventional therapy at time of diagnosis and 6.3% of patients were judged inoperable at the time of first presentation. Nearly 50% of cases with AHD were RHDs followed by dilated cardiomyopathy and pulmonary hypertension without underlying CHD. CONCLUSIONS: The spectrum of CHD and AHD from one centre in Tanzania is comparable to findings reported in other countries from the African continent. Echocardiography is a valuable diagnostic tool and the widespread use of it should be enhanced to diagnose heart diseases in a large number and reasonable time. Most patients present late and majority is in need of surgical or interventional treatment, which is still not readily available. Untreated heart diseases contribute substantially to morbidity and mortality during infancy and childhood. Adequate cardiac services should be established and strengthened.

C2 Fractures in the Elderly: Single-Center Evaluation of Risk Factors for Mortality.

Study Design: Retrospective cohort study. Purpose: The aim of this study was to identify features associated with increased mortality risk in traumatic C2 fractures in the elderly, including measures of comorbidity and frailty. Overview of Literature: C2 fractures in the elderly are of increasing relevance in the setting of an aging global population and have a high mortality rate. Previous analyzes of risk factors for mortality have not included the measures of comorbidity and/or frailty, and no local data have been reported to date. Methods: This study comprises a retrospective review of 70 patients of age >65 years at Waikato Hospital, New Zealand with traumatic C2 fractures identified on computed tomography between 2010 and 2016. Demographic details, medical history, laboratory results on admission, mechanism of injury, and neurological status on presentation were recorded. Medical comorbidities were also detailed allowing calculation of the Charlson Comorbidity Index (CCI) and the modified Frailty Index (mFI). Results: The most common mechanism of injury was a fall from standing height (n=52, 74.3%). Mortality rates were 14.3% (n=10) at day 30, and 35.7% (n=25) at 1 year. Bivariate analysis showed that both CCI and mFI correlated with 1-year mortality rates. Reduced albumin and hemoglobin levels were also associated with 30-day and 1-year mortality rates. Forward stepwise logistic regression models determined CCI and low hemoglobin as predictors of mortality within 30 days, whereas CCI, low albumin, increased age, and female gender predicted mortality at 1 year. Conclusions: The CCI was a useful tool for predicting mortality at 1 year in the patient cohort. Other variables, including common laboratory markers, can also be used for risk stratification, to initiate timely multidisciplinary management, and prognostic counseling for patients and family members.

Managing taste and odour metabolite production in drinking water reservoirs: The importance of ammonium as a key nutrient trigger.

Taste and odour (T&O) compounds (most commonly 2-MIB and Geosmin) in drinking water are becoming an increasingly global problem for water management. Here, the trigger(s) for 2-MIB and Geosmin production were investigated in Plas Uchaf reservoir (North Wales, UK) with detailed water sample analysis between 2015 and 2016. Historical abstraction data from this reservoir and 4 reservoirs in Somerset (England, UK) were compared statistically using Self-Organising Map (SOM) analysis. In-reservoir measurements (2015-2016) revealed an 85% reduction in ammonium from the primary external loading source led to lower 2-MIB and Geosmin concentrations, with peak concentrations of 2-MIB declining from 60 to 21  ng l-1 and Geosmin declining from 140 to 18  ng l-1. No other measured water chemistry parameter showed a significant difference between years. The SOM results support the in-reservoir findings, revealing 2-MIB and Geosmin to be associated with high ammonium relative to nitrate for all 5 reservoirs. We conclude that ammonium is key for stimulating cyanobacterial productivity and production of T&O compounds. Whilst it is well understood that adequate availability of phosphorus is required for rapid growth in cyanobacteria, and hence should still be considered in management decisions, we suggest that monitoring sources and concentrations of ammonium is key for managing T&O outbreaks in drinking water reservoirs.

C2 Fractures in the Elderly: Single-Center Evaluation of Risk Factors for Mortality

STUDY DESIGN: Retrospective cohort study. PURPOSE: The aim of this study was to identify features associated with increased mortality risk in traumatic C2 fractures in the elderly, including measures of comorbidity and frailty. OVERVIEW OF LITERATURE: C2 fractures in the elderly are of increasing relevance in the setting of an aging global population and have a high mortality rate. Previous analyzes of risk factors for mortality have not included the measures of comorbidity and/or frailty, and no local data have been reported to date. METHODS: This study comprises a retrospective review of 70 patients of age >65 years at Waikato Hospital, New Zealand with traumatic C2 fractures identified on computed tomography between 2010 and 2016. Demographic details, medical history, laboratory results on admission, mechanism of injury, and neurological status on presentation were recorded. Medical comorbidities were also detailed allowing calculation of the Charlson Comorbidity Index (CCI) and the modified Frailty Index (mFI). RESULTS: The most common mechanism of injury was a fall from standing height (n=52, 74.3%). Mortality rates were 14.3% (n=10) at day 30, and 35.7% (n=25) at 1 year. Bivariate analysis showed that both CCI and mFI correlated with 1-year mortality rates. Reduced albumin and hemoglobin levels were also associated with 30-day and 1-year mortality rates. Forward stepwise logistic regression models determined CCI and low hemoglobin as predictors of mortality within 30 days, whereas CCI, low albumin, increased age, and female gender predicted mortality at 1 year. CONCLUSIONS: The CCI was a useful tool for predicting mortality at 1 year in the patient cohort. Other variables, including common laboratory markers, can also be used for risk stratification, to initiate timely multidisciplinary management, and prognostic counseling for patients and family members.

Comparison of two pressurisers for cementation of the proximal femur.

PURPOSE: To compare pressures generated by 2 different cement pressurisers at various locations in the proximal femur. METHODS: Two groups of 5 synthetic femurs were used, and 6 pressure sensors were placed in the femur at 20-mm intervals proximally to distally. Cement was filled into the femoral canal retrogradely using a cement gun with either the half-moon pressuriser or the femoral canal pressuriser. Maximum pressures and pressure time integrals (cumulative pressure over time) of the 2 pressurisers were compared. RESULTS: At all sensors, the half-moon pressuriser produced higher maximum pressures and pressure time integrals than the femoral canal pressuriser, but the difference was significant only at sensor 1 (proximal femur). This may result in reduced cement interdigitation in the proximal femur. CONCLUSION: The half-moon pressuriser produced higher maximum cementation pressures and pressure time integrals than the femoral canal pressuriser in the proximal femur region, which is critical for rotational stability of the implant and prevention of implant fracture.

Periprosthetic fracture torque for short versus standard cemented hip stems: an experimental in vitro study.

In an attempt to preserve proximal femoral bone stock and achieve a better fit in smaller femora, especially in the Asian population, several new shorter stem designs have become available. We investigated the torque to periprosthetic femoral fracture of the Exeter short stem compared with the conventional length Exeter stem in a Sawbone model. Forty-two stems; 21 shorter and 21 conventional stems both with three different offsets were cemented in a composite Sawbone model and torqued to fracture. Results showed that Sawbone femurs break at a statistically significantly lower torque to failure with a shorter compared to conventional-length Exeter stem of the same offset. Both standard and short-stem designs are safe to use as the torque to failure is 7-10 times that seen in activities of daily living.

Exeter short stems compared with standard length Exeter stems: experience from the Australian Orthopaedic Association National Joint Replacement Registry.

The standard Exeter stem has a length of 150 mm with offsets 37.5 to 56 mm. Shorter stems of lengths 95, 115 and 125 mm with offsets 35.5 mm or less are available for patients with smaller femurs. Concern has been raised regarding the behavior of the smaller implants. This paper analyzed data from the Australian Orthopaedic Association National Joint Replacement Registry comparing survivorship of stems of offset 35.5 mm or less with the standard stems of 37.5 mm offset or greater. At 7 years, there was no significant difference in the cumulative percent revision rate in the short stems (3.4%, 95% CI 2.4-4.8%) compared with the standard length stems (3.5%, 95% CI 3.3-3.8%) despite its use in a greater proportion of potentially more difficult developmental dysplasia of the hip cases.

Characterization of a dynamic multi-leaf collimator for stereotactic radiotherapy applications.

The Apex® dynamic mini-multileaf collimator has recently been released by Elekta and attaches directly to the linear accelerator head. This paper details the work and results obtained in characterizing this mini-MLC for stereotactic usage within our department. A range of mechanical and dosimetric characteristics were investigated which included inter and intra leaf leakage, light/radiation field congruence, leaf position reproducibility, radiation penumbra, total scatter factors and mechanical rotational stability with the additional mini-MLC weight.

Radiation safety implications of 131I treatment in a patient with Grave's disease undergoing home hemodialysis.

The radiation safety implications following the administration of 131I for the treatment of Grave's disease to a patient undergoing home-based renal dialysis was investigated. External dose-rate measurements from the patient revealed a peak value at around day 2, post administration. The effective half-life was determined as 6.5 d. From day 3, the clearance of 131I was observed to be fairly constant and equated to 2.7% per day or 5.4% per dialysis session. From this the biological half-life was determined as 15 d. Radiation monitoring of the dialysis unit, disposables, and bed linen found no detectable contamination. For the purpose of useful protection, at a distance of 1 m from the patient, the average dose rate over the effective treatment duration was determined to be 8 microSv h(-1) and at 2 m distance, 2.6 microSv h(-1). Thus, in order to keep below a level of dose constraint of 3 mSv the total allowable time spent at 1 m would be 375 h or 15 h per day. To comply with a 1-mSv constraint, the average daily exposure allowable at 1 m would be 5 h per day. Neither of these time limits would be difficult to achieve for the majority of situations with fairly modest behavioral constraints. Initial discharge concentration rates into the waste water system are estimated at 200 MBq m(-3) and therefore might need to be considered depending upon the regulatory environment.

Shielding properties of fibre cement wallboard.

Transmission data for a fibre cement wallboard (villaboard) are determined for use in diagnostic shielding designs. Villaboard is found to be more attenuating than plasterboard e.g. 9 mm of villaboard is equivalent to 16 mm of plasterboard.

Insect cells as substrates for biologicals.

Various methods for the growth of insect cells and the production of recombinant human beta-interferon (rHu beta-IFN) by insects cells, Spodoptera frugiperda, IPL-Sf-21AE after infection with recombinant AcNPV are described. Using a suspension perfusion Biospin filter culture system, an IPL-Sf-21AE cell line was propagated in a semi-controlled environment. To obtain and maintain high cell densities and viabilities in this system, the culture medium for suspension methods was modified by supplementing with ZnSO4, ALCl3, methyl cellulose and Darvan #2. Using these improved conditions, multiple harvests of rHu beta-IFN were collected in the cell culture supernatant for downstream processing.

Perilymphatic fistula in children with preexisting sensorineural hearing loss.

Progression of preexisting sensorineural hearing loss (SNHL) in infants and children has been considered an indication for fistula exploration: is this approach warranted? On exploring 36 middle ears in 26 such children, we found a perilymphatic fistula (PLF) in four ears (11%). Although there was radiographic evidence of inner-ear deformity in one half of these children, a definite fistula was found in only four of 18 radiographically abnormal ears explored (22%). Even in the four patients with a history of an "event" that could implicate a fistula such as exertion or barotrauma, a fistula was found in only one. There are a number of possible causes for progression of a preexisting SNHL, and surgical exploration of the middle ear should not be recommended on the basis of progression alone. Instead, exploration for a suspected PLF should be strongly considered when there is also a history of an "event", and/or radiographic evidence of inner-ear abnormalities. Even under these conditions, one should be aware that fistulae are not likely to be found.

A Histochemical study of the coronary vasculature in euthyroid and hyperthyroid rats.

Coronary arteries and arterioles in the left and right ventricles from normal and hyperthyroid rats were examined histochemically to determine and to compare their metabolic activities. The test animals were made hyperthyroid by administration of desiccated thyroid for 8-10 weeks. Using histochemical techniques, selected enzymes and components of key metabolic pathways were examined. These pathways included an evaluation of aerobic (oxidative phosphorylation, Kreb's cycle and respiratory chain) and anaerobic metabolic capacity, hexose-monophosphate shunt activity, amounts of deoxyribonucleic and ribonucleic acids present and activity of beta-oxidation of fatty acids. Our results indicate that normal coronary arteriolar metabolism is predominantly aerobic. The findings also suggest a reduction in aerobic metabolism with an accompanying increase in anaerobic potential in the hyperthyroid coronary arterioles. Thus, during thyrotoxicosis, the coronary arterioles may partially shift from aerobic to anaerobic metabolism. Moreover, in both the normal and thyrotoxic rat heart, the coronary microvasculature appears quite stable with little cell proliferation. In contrast, both the control and hyperthyroid rat coronary arteries appear to utilize primarily anaerobic pathways, while the control and hyperthyroid myocardium seem highly dependent upon aerobic metabolism. The tremendous reduction in glucose-6-phosphate dehydrogenase activity in hyperthyroid, when compared to normal coronary arteries and some larger arterioles, implies a reduced capacity for nucleic acid and protein synthesis in the test animals.