The phytosociology of the grasslands of the Ba and Ib land types in the Pretoria–Witbank–Heidelberg area

An analysis of the plant communities of the grasslands of the Pretoria–Witbank–Heidelberg area is presented. Relevés were compiled in 148 stratified random sample plots. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed fourteen plant communities, and a hierarchical classification, description and ecological interpretation of these plant communities are presented. Each of these plant communities may be regarded as an entity with a unique species composition, and with specific environmental relationships and an inherent forage production potential. The identification, classification and description of these plant communities are not only important for management purposes, but also for the preservation of biotic diversity

Evaluation of in vivo techniques for the determination of apparent ileal amino acid digestibilities in feedstuffs for piglets

Three in vivo techniques were evaluated in terms of their suitability for determination of the apparent ileal amino acid digestibility (AID) of protein sources for piglets. The techniques were: ileo-rectal anastomosis (IRA), cannulation at the distal ileum and a slaughter technique. A standard diet and three diets in which 20% of the standard diet was substituted with either skim milk powder (SMP), fish meal or roasted full-fat soya beans (FFS) were used. Piglets were weaned at 21 days of age, and the respective diets were fed in 24 equal hourly portions per day from days 29-37. Ileal digesta was collected from day 33-37 in IRA and cannulated piglets. Piglets used for the slaughter technique were killed at 37 days of age and ileal digesta was collected. Chromium III oxide was used as an indigestible marker with all three techniques. Although AID means did not differ (p > 0.05) between the different techniques, the cannulation technique resulted in the lowest variation (standard error of the mean) of all treatments (8.2 vs 13.7 and 14.1 for the slaughter and IRA-techniques respectively). AID means obtained using the cannula technique were 1.8 percentage units higher for the SMP diet than values obtained using the other techniques (83.2 versus 81.4 %), and up to 9.3 percentage units higher for the FFS diet (75.4 versus 66.1 %). Growth data suggested that the cannulation technique caused less trauma for the piglets than the IRA-technique. IRA-piglets had not yet regained their initial weaning weight by 37 days of age, while the other piglets gained weight over the trial period. The cannulation technique is the most attractive method for use with piglets in terms of the lower variation in digestibility values. Practical aspects such as ease of handling and sampling, surgical trauma and piglet stress, are also important and contribute to the selection of the cannula technique as the most appropriate. (South African Journal of Animal Science, 2000, 30(1): 7-15

Tocilizumab in patients admitted to hospital with COVID-19 (RECOVERY): a randomised, controlled, open-label, platform trial

Background: In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hospital with COVID-19 with both hypoxia and systemic inflammation. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. Those trial participants with hypoxia (oxygen saturation <92% on air or requiring oxygen therapy) and evidence of systemic inflammation (C-reactive protein ≥75 mg/L) were eligible for random assignment in a 1:1 ratio to usual standard of care alone versus usual standard of care plus tocilizumab at a dose of 400 mg–800 mg (depending on weight) given intravenously. A second dose could be given 12–24 h later if the patient's condition had not improved. The primary outcome was 28-day mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). Findings: Between April 23, 2020, and Jan 24, 2021, 4116 adults of 21 550 patients enrolled into the RECOVERY trial were included in the assessment of tocilizumab, including 3385 (82%) patients receiving systemic corticosteroids. Overall, 621 (31%) of the 2022 patients allocated tocilizumab and 729 (35%) of the 2094 patients allocated to usual care died within 28 days (rate ratio 0·85; 95% CI 0·76–0·94; p=0·0028). Consistent results were seen in all prespecified subgroups of patients, including those receiving systemic corticosteroids. Patients allocated to tocilizumab were more likely to be discharged from hospital within 28 days (57% vs 50%; rate ratio 1·22; 1·12–1·33; p<0·0001). Among those not receiving invasive mechanical ventilation at baseline, patients allocated tocilizumab were less likely to reach the composite endpoint of invasive mechanical ventilation or death (35% vs 42%; risk ratio 0·84; 95% CI 0·77–0·92; p<0·0001). Interpretation: In hospitalised COVID-19 patients with hypoxia and systemic inflammation, tocilizumab improved survival and other clinical outcomes. These benefits were seen regardless of the amount of respiratory support and were additional to the benefits of systemic corticosteroids. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research

Convalescent plasma in patients admitted to hospital with COVID-19 (RECOVERY): a randomised controlled, open-label, platform trial

Background: Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods: This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings: Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive convalescent plasma and were assigned to either the convalescent plasma group or the usual care group. There was no significant difference in 28-day mortality between the two groups: 1399 (24%) of 5795 patients in the convalescent plasma group and 1408 (24%) of 5763 patients in the usual care group died within 28 days (rate ratio 1·00, 95% CI 0·93–1·07; p=0·95). The 28-day mortality rate ratio was similar in all prespecified subgroups of patients, including in those patients without detectable SARS-CoV-2 antibodies at randomisation. Allocation to convalescent plasma had no significant effect on the proportion of patients discharged from hospital within 28 days (3832 [66%] patients in the convalescent plasma group vs 3822 [66%] patients in the usual care group; rate ratio 0·99, 95% CI 0·94–1·03; p=0·57). Among those not on invasive mechanical ventilation at randomisation, there was no significant difference in the proportion of patients meeting the composite endpoint of progression to invasive mechanical ventilation or death (1568 [29%] of 5493 patients in the convalescent plasma group vs 1568 [29%] of 5448 patients in the usual care group; rate ratio 0·99, 95% CI 0·93–1·05; p=0·79). Interpretation: In patients hospitalised with COVID-19, high-titre convalescent plasma did not improve survival or other prespecified clinical outcomes. Funding: UK Research and Innovation (Medical Research Council) and National Institute of Health Research

The Significance of Prelabour Type 11 .Deceleration of Fetal Heart Rate in Relation to Braxton-Hicks Contractions

During prelabour cardiotocography on 450 high risk antenatal patients, painless uterine contractions (BraxtonHicks) were recorded in 4 patients, who also showed a type 11 deceleration pattern. Two fetuses died and 2 were saved. In the 2 who died there was a delay of more than 12 hours between first observation and delivery, while in the 2 who were saved, immediate Caesarean section was performed. It is suggested that the sign of late deceleration in relation to Braxton-Hicks contractions is a preterminal manifestation of acute-on-chronic fetal distress, and the appropriate management should be immediate Caesarean section, whatever the gestation. Antenatal cardiotocography might therefore have a place in the assessment of the 'very small for gestational age fetus and an irritable uterus. This approach could ensure survival but not necessarily quality

The impact of number of metaphase II oocytes and patient age on the multiple pregnancy rate in a gamete intrafallopian transfer (GIFT) programme

ArticleThe original publication is available at http://www.samj.org.zaObjective. To study the effect of number of oocytes transferred and patient age on gamete intrafallopian transfer (GIFT) pregnancy and multiple pregnancy rates. Patients. GIFT patients from our clinical database were retrospectively analysed. They were divided into two age groups, under 38 years old and 38 and older. The patients were further divided into two subgroups, 3 oocytes and 4 or more oocytes transferred. Pregnancy rates and multiple pregnancy rates were calculated for the two groups. Statistical methods. The under-38 group's subgroups were nominated as group 1 (3 oocytes) and group 2 (s4 oocytes) and the 38-and-over group's subgroups as group A (3 oocytes) and group B (s4 oocytes). The x2 test and Fisher's exact test were used to analyse the data. Results. The ongoing pregnancy rate in group 1 was 28.8% (150/521) as opposed to 20.6% (96/465) in group 2 (P < 0.0045). The multiple pregnancy rate in group 1 was 14.0% (21/150) as opposed to 33.3% (32/96) in group 2 (P < 0.005). The triplet or higher-order pregnancy rate in group 1 was 2.7% (4/150) as opposed to 8.3% (8/96) in group 2 (not statistically significant). The ongoing pregnancy rate in group A was 11.8% (16/136) as opposed to 11.0% (8/73) in group B (NS). The multiple pregnancy rate in group A was 12.5% (2.16) as opposed to 25.0% (2/8) in group B (NS). Conclusions. These data show that transfer of more than 3 oocytes does not produce better pregnancy rates in either the under-38 or the 38-and-over group. The multiple pregnancy rate is, however, significantly higher when 4 or more oocytes are transferred in a GIFT programme. Transfer of more than 3 oocytes should therefore be restricted to carefully selected patients.Publisher’s versio

Intracytoplasmic sperm injection with testicular spermatozoa in men with azoospermia

Purpose: The aim of the study was to gain an insight into the optimal management of the infertile couple with the husband suffering from azoospermia. Methods: One hundred and forty-two intracytoplasmic sperm injection (ICSI) cycles performed with testicular extracted spermatozoa were retrospectively analysed. The following factors were investigated for their possible influence on fertilization, cleavage, damage, pregnancy, and ongoing pregnancy rates; the use of fresh, cryopreserved, and preincubated (24 h) spermatozoa and the etiology of the husbands' azoospermia (obstructive and nonobstructive). All microinjections were performed with apparently normal spermatozoa-a head with a tail of normal length. In 116 cycles at least two embryos were available for transfer. Results: The overall fertilization, clinical pregnancy, and ongoing pregnancy rates obtained for the 116 cycles were 65.0, 30.2, and 22.4% respectively. Similar outcomes were obtained for cycles using fresh testicular and cryopreserved testicular spermatozoa. Similarly, no significant differences were obtained between the cycles using spermatozoa from obstructive or nonobstructive azoospermic patients. An increase in motility after a 24-h preincubation was observed, and although this group was relatively small (n = 17), a significant improvement in fertilization (73.7%) and pregnancy (53.9%) rate was obtained when the testicular sample was preincubated for 24 h. This improvement prevailed in the obstructive azoospermic group, but was less pronounced in nonobstructive patients. Conclusions: This study shows that the outcome of fresh and frozen-thawed testicular spermatozoa in ICSI is comparable, obstructive and nonobstructive etiologies perform the same, and that preincubation of testicular spermatozoa results in increased fertilization and pregnancy rates. All testicular biopsies are therefore performed the day before oocyte retrieval, superfluous spermatozoa cryopreserved, and the remaining testicular homogenate preincubated for the 24 h prior to oocyte retrieval. With this regime, most azoospermic patients are treated successfully, irrespective of the use of fresh or frozen-thawed spermatozoa from obstructive or nonobstructive cases.Articl