Congenital anomalies in low- and middle-income countries: the unborn child of global surgery.

Surgically correctable congenital anomalies cause a substantial burden of global morbidity and mortality. These anomalies disproportionately affect children in low- and middle-income countries (LMICs) due to sociocultural, economic, and structural factors that limit the accessibility and quality of pediatric surgery. While data from LMICs are sparse, available evidence suggests that the true human and financial cost of congenital anomalies is grossly underestimated and that pediatric surgery is a cost-effective intervention with the potential to avert significant premature mortality and lifelong disability

A systematic review of the evidence for single stage and two stage revision of infected knee replacement

BACKGROUND: Periprosthetic infection about the knee is a devastating complication that may affect between 1% and 5% of knee replacement. With over 79 000 knee replacements being implanted each year in the UK, periprosthetic infection (PJI) is set to become an important burden of disease and cost to the healthcare economy. One of the important controversies in treatment of PJI is whether a single stage revision operation is superior to a two-stage procedure. This study sought to systematically evaluate the published evidence to determine which technique had lowest reinfection rates. METHODS: A systematic review of the literature was undertaken using the MEDLINE and EMBASE databases with the aim to identify existing studies that present the outcomes of each surgical technique. Reinfection rate was the primary outcome measure. Studies of specific subsets of patients such as resistant organisms were excluded. RESULTS: 63 studies were identified that met the inclusion criteria. The majority of which (58) were reports of two-stage revision. Reinfection rated varied between 0% and 41% in two-stage studies, and 0% and 11% in single stage studies. No clinical trials were identified and the majority of studies were observational studies. CONCLUSIONS: Evidence for both one-stage and two-stage revision is largely of low quality. The evidence basis for two-stage revision is significantly larger, and further work into direct comparison between the two techniques should be undertaken as a priority

Effects of light path lengths and initial culture density on the cultivation of Chaetoceros muelleri (Lemmermann, 1898)

WOS: 000181129300033In the cultivation of a marine diatom Chaetoceros muelleri (Lemmermann, 1898), flat plate vertical glass reactors with light path lengths of 1 or 3 cm were used in the laboratory under a constant photon flux density (PFD) of 190 mumol photon m(-2) s(-1). In the first experiment, equal inocula were added in the two bioreactors (1 and 3 cm light path); by the end of the second day, cell concentration was low in the 1-cm light path bioreactor, possibly indicating photoinhibition, since growth of the culture increased in the 3-cm light path bioreactor. As for in the second trial, the areal volumes were equal, that is, the cell concentration was increased three-fold in 1 cm light path to equalize the areal optic densities in both reactors. After the harvest started, average of the volumetric output rates in 1 cm (P-V1 (cm)) and 3 cm light paths (P-V3 (cm)) were calculated to be 0.22 and 0.10 g l(-1) day(-1), and areal output rates in 1 cm (P-A1 (cm)) and 3 cm (P-A3 (cm)) light paths were calculated to be 1.80 and 2.53 g m(-2) day(-1), respectively. The optimal population density was obtained by a daily harvest of 5% of culture volume to be 2.39 g m(-2) day(-1) in 1 cm light path and 3.27 g m(-2) day(-1) in 3 cm light path. Light path length of 3 cm was found optimal in both with low and high initial cell densities. (C) 2003 Elsevier Science B.V. All rights reserved

Photon irradiance required to support optimal growth and interrelations between irradiance and pigment composition in the green alga Haematococcus pluvialis

WOS: 000230429100009The aim of the work was to find the optimal photon irradiance for the growth of green cells of Haematococcus pluvialis and to study the interrelations between changes in photochemical parameters and pigment composition in cells exposed to photon irradiances between 50 and 600 mu mol m(-2) s(-1) and a light: dark cycle of 12: 12 h. Productivity of cultures increased with irradiance. However, the rate of increase was higher in the range 50 - 200 mu mol(-2) s(-1). The carotenoid content increased with increasing irradiance, while the chlorophyll content decreased. The maximum quantum yield of PSII (F-v/F-m) gradually declined from 0.76 at the lowest irradiance of 50 mu mol(-2) s(-1) to 0.66 at 600 mu mol(-2) s(-1). Photosynthetic activity showed a drop at the end of the light period, but recovered fully during the following dark phase. A steep increase in non-photochemical quenching was observed when cultures were grown at irradiances above 200 mu mol(-2) s(-1). A sharp increase in the content of secondary carotenoids also occurred above 200 mu mol m(-2) s(-1). According to our results, with H. pluvialis green cells grown in a 5-cm light path device, 200 mu mol(-2) s(-1) was optimal for growth, and represented a threshold above which important changes in both photochemical parameters and pigment composition occurred

Interplay between photochemical activities and pigment composition in an outdoor culture of Haematococcus pluvialis during the shift from the green to red stage

9th International Conference on Applied Algology -- MAY 26-30, 2002 -- AGUADULCE, SPAINWOS: 000183045600007The transfer of laboratory cultures of H. pluvialis to high irradiance outdoors caused a substantial decline in the maximum quantum yield of photosystem II (PSII), from 0.65 in the morning to 0.45 at midday, as measured by the ratio of variable to maximum fluorescence yields (F(v)/F(m)), and a steep rise in non-photochemical quenching (NPQ). Chlorophyll fluorescence induction curves of morning samples showed a clear I-step, reflecting a certain PSII heterogeneity. Single turnover flash measurements on samples taken from the outdoor photobioreactor in the middle of day showed an increase in the reoxidation time constant of the reduced plastoquinone Q(A)(-), i.e., the time required for electron transfer from the primary plastoquinone acceptor of PSII Q(A)(-) to the secondary plastoquinone acceptor Q(B). Photosynthesis rates were almost constant during the day. Along with the increase in non-photochemical quenching, there was a slight increase in zeaxanthin and antheraxanthin contents and decrease in violaxanthin, showing the presence of an operative xanthophyll cycle in this microalga. A marked increase of secondary carotenoids was found at the end of the first day of exposure to sunlight, mainly astaxanthin monoester, which reached 15.5% of the total carotenoid content. Though cells turned reddish during the second day, the decline in the fluorescence parameter F(v)/F(m) in the middle of the day was less than during the first day, and there was no further increase in the value for NPQ. Similar behaviour was observed during the third day when the culture was fully red. After four days of exposure to sunlight, the dry weight reached 800 mg L(-1) and the concentration of secondary carotenoids (81% astaxanthin monoester) reached 4.4% dry weight.Int Soc Appl Phyco

Noxious stimulation in children receiving general anaesthesia evokes an increase in delta frequency brain activity.

More than 235,000children/year in the UK receive general anaesthesia, but it is unknown whether nociceptive stimuli alter cortical brain activity in anaesthetised children. Time-locked electroencephalogram (EEG) responses to experimental tactile stimuli, experimental noxious stimuli, and clinically required cannulation were examined in 51 children (ages 1-12years) under sevoflurane monoanaesthesia. Based on a pilot study (n=12), we hypothesised that noxious stimulation in children receiving sevoflurane monoanaesthesia would evoke an increase in delta activity. This was tested in an independent sample of children (n=39), where a subset (n=11) had topical local anaesthetic applied prior to stimulation. A novel method of time-locking the stimuli to the EEG recording was developed using an event detection interface and high-speed camera. Clinical cannulation evoked a significant increase (34.2±8.3%) in delta activity (P=0.042), without concomitant changes in heart rate or reflex withdrawal, which was not observed when local anaesthetic was applied (P=0.30). Experimental tactile (P=0.012) and noxious (P=0.0099) stimulation also evoked significant increases in delta activity, but the magnitude of the response was graded with stimulus intensity, with the greatest increase evoked by cannulation. We demonstrate that experimental and clinically essential noxious procedures, undertaken in anaesthetised children, alter the pattern of EEG activity, that this response can be inhibited by local anaesthetic, and that this measure is more sensitive than other physiological indicators of nociception. This technique provides the possibility that sensitivity to noxious stimuli during anaesthesia could be investigated in other clinical populations