Higher rates of anatomical insertion of medial hamstring tendon regeneration post-anterior cruciate ligament reconstruction with stump preservation graft harvesting technique: A prospective, randomised, double-blinded clinical trial with magnetic resonance imaging evaluation.

OBJECTIVE(S): The purpose of this study was to compare the regeneration of semitendinosus and gracilis tendons from two different graft harvesting techniques, which are the stump preservation and conventional graft harvesting techniques. We hypothesised that the stump preservation graft harvesting technique, which preserved the distal attachment of tendons at their insertion, would facilitate anatomical regeneration to the pes anserinus. METHODS: This is a prospective, randomised, double-blinded study whereby thirty consecutive patients who underwent single bundle anterior cruciate ligament reconstruction with ipsilateral semitendinosus and gracilis autografts were recruited. The patients were randomly assigned to the stump preservation group (14 patients) or conventional group (16 patients). Magnetic resonance imaging (MRI) evaluation was performed preoperatively and at six months post-operatively. RESULTS: At 6-month follow-up, MRI evaluations showed a higher percentage of insertion of regenerated semitendinosus and gracilis at the pes anserinus in the stump preservation group (75.0%) than that in the conventional group (68.8%). There was a significantly higher proximal shift of the musculotendinous junction of semitendinosus (5.70 â€‹cm versus 3.36 â€‹cm, p â€‹= â€‹0.029) and gracilis (5.28 â€‹cm versus 3.16 â€‹cm, p â€‹= â€‹0.045) in the conventional group post-operatively. CONCLUSION: The stump preservation technique yields a higher percentage of anatomical insertion of regenerated tendons and a lesser amount of proximal shift of the musculotendinous junction. LEVEL OF EVIDENCE: III - Prospective study with up to two negative criteria.

Impact of the 2020 New Zealand COVID-19 lockdown on participants in a community-based, peer-led fall prevention program.

OBJECTIVES: To explore the impacts of the 2020 New Zealand COVID-19 lockdown on peer-led Steady as You Go (SAYGO) fall prevention exercise classes and members, and to develop recommendations for mitigating impacts during future lockdowns. METHODS: Semi-structured phone interviews were conducted with 20 SAYGO program participants and managers following the first COVID-19 lockdown in New Zealand. Interviews were audio-recorded, transcribed verbatim and analysed using the General Inductive Approach. RESULTS: Participants were between 67 and 88 years of age, predominantly female (90%) and NZ European (80%), with one participant identifying as NZ Maori. Three themes were constructed from the analysis: Personal Function and Well-Being, Class Functioning and Logistics, and Future Strategies for Classes During Prospective Lockdowns. Participants used a range of strategies to stay connected with each other and continue the SAYGO exercises at home. Most participants and peer-leaders reported that they maintained physical function during lockdown, although some had feelings of psychological distress and social isolation. Contact systems and resource distribution varied substantially between groups. Classes resumed post-lockdown with only minor modifications and slightly decreased attendance. CONCLUSIONS: Overall, members of this peer-led model of fall prevention classes demonstrated resilience during the COVID-19 lockdown, despite some challenges. We propose three recommendations to address the challenges of maintaining existing peer-led exercise classes in the context of prospective lockdowns: (1) develop a comprehensive contact detail register and plans for each group; (2) delivery of modified exercise classes remotely over lockdown; and (3) implementation of a nationwide IT education and resource program for older adults.

Blomia tropicalis-Specific TCR Transgenic Th2 Cells Induce Inducible BALT and Severe Asthma in Mice by an IL-4/IL-13-Dependent Mechanism.

Previous studies have highlighted the importance of lung-draining lymph nodes in the respiratory allergic immune response, whereas the lung parenchymal immune system has been largely neglected. We describe a new in vivo model of respiratory sensitization to Blomia tropicalis, the principal asthma allergen in the tropics, in which the immune response is focused on the lung parenchyma by transfer of Th2 cells from a novel TCR transgenic mouse, specific for the major B. tropicalis allergen Blo t 5, that targets the lung rather than the draining lymph nodes. Transfer of highly polarized transgenic CD4 effector Th2 cells, termed BT-II, followed by repeated inhalation of Blo t 5 expands these cells in the lung >100-fold, and subsequent Blo t 5 challenge induced decreased body temperature, reduction in movement, and a fall in specific lung compliance unseen in conventional mouse asthma models following a physiological allergen challenge. These mice exhibit lung eosinophilia; smooth muscle cell, collagen, and goblet cell hyperplasia; hyper IgE syndrome; mucus plugging; and extensive inducible BALT. In addition, there is a fall in total lung volume and forced expiratory volume at 100 ms. These pathophysiological changes were substantially reduced and, in some cases, completely abolished by administration of neutralizing mAbs specific for IL-4 and IL-13 on weeks 1, 2, and 3. This IL-4/IL-13-dependent inducible BALT model will be useful for investigating the pathophysiological mechanisms that underlie asthma and the development of more effective drugs for treating severe asthma.

Intracellular glycerol accumulation in light-limited Dunaliella tertiolecta culture is determined by partitioning of glycerol across the cell membrane.

Dunaliella accumulates intracellular glycerol to counterbalance the extracellular salinity. In N-limited chemostat cultures of D. tertiolecta, total glycerol production (sum of intracellular and extracellular) and intracellular glycerol content were proportional to the salinity of the culture medium. In the light-limited D. tertiolecta culture, total glycerol output (sum of intracellular and extracellular) was relatively constant at different salinities (0.5 and 2.0 M), while the intracellular glycerol content was proportional to the culture medium salinity, that is, the cells released less glycerol into the culture medium, rather than de novo synthesis of glycerol at high culture medium salinity. The study implies different regulatory mechanisms in the accumulation of intracellular glycerol in N-limited and light-limited D. tertiolecta in response to salinity.

Occurrence of glycerol uptake in Dunaliella tertiolecta under hyperosmotic stress.

The unicellular halotolerant green alga species Dunaliella are able to proliferate in extremely varied salinities by synthesizing intracellular glycerol and adjusting the cell shape and volume. However, some marine Dunaliella species such as Dunaliella tertiolecta are not able to regulate cell volume as an immediate response to counter external osmotic shock. Here we report that a rapid shock-response mechanism is present in Dunaliella tertiolecta, involving uptake of exogenous glycerol in response to hyperosmotic shock without changing cell volume, and this glycerol uptake activity is associated with the Dunaliella tertiolecta glycerol uptake protein 1 (DtGUP1) gene, which belongs to the membrane-bound O-acyltransferase. The mutant DtGUP1-E, in which the DtGUP1 gene is silenced, displayed an inability to take up glycerol from the medium and showed cell death under hyperosmotic shock. To our knowledge, this is the first time a gene product has been reported in Dunaliella tertiolecta that is involved in glycerol uptake activity under hyperosmotic stress.

Expression of the Chlamydomonas reinhardtii sedoheptulose-1,7-bisphosphatase in Dunaliella bardawil leads to enhanced photosynthesis and increased glycerol production.

Bioengineering of photoautotrophic microalgae into CO(2) scrubbers and producers of value-added metabolites is an appealing approach in low-carbon economy. A strategy for microalgal bioengineering is to enhance the photosynthetic carbon assimilation through genetically modifying the photosynthetic pathways. The halotolerant microalgae Dunaliella possess a unique osmoregulatory mechanism, which accumulates intracellular glycerol in response to extracellular hyperosmotic stresses. In our study, the Calvin cycle enzyme sedoheptulose 1,7-bisphosphatase from Chlamydomonas reinhardtii (CrSBPase) was transformed into Dunaliella bardawil, and the transformant CrSBP showed improved photosynthetic performance along with increased total organic carbon content and the osmoticum glycerol production. The results demonstrate that the potential of photosynthetic microalgae as CO(2) removers could be enhanced through modifying the photosynthetic carbon reduction cycle, with glycerol as the carbon sink.

Medical students' choice of specialty and factors determining their choice: a cross-sectional questionnaire survey in Melaka-Manipal Medical College, Malaysia.

Information about medical students' choice of specialty can be helpful for planning health manpower. However, such information from medical students in Malaysian medical schools is lacking. We carried out a cross-sectional questionnaire survey among fourth- and fifth-year medical undergraduate students at Melaka-Manipal Medical College. A total of 425 students responded to the survey questionnaire. Nearly a quarter of the students indicated internal medicine as their choice of specialty. Other choices were general surgery (13.2%), pediatrics (11.3%), orthopedics (12.7%) and obstetrics & gynecology (Ob/Gyn) (12.1%). Female students (OR 1.91; 95% CI 1.18-3.08), fourth-year students (OR 1.9; 95% CI 1.15-3.12), and students who reported a higher self-rated knowledge of their subject of choice were more likely to choose internal medicine and allied specialties (OR 1.53; 95% CI 1.07-2.19). The influence of teaching faculty and consultants at the teaching hospitals (74.4%) and inspiration obtained during clinical postings (71.9%) were the factors which were rated by the most students as 'important' for choosing a specialty. About half of the students intended to pursue their postgraduate studies in Malaysia, most of the rest in the United Kingdom or Australia. While internal medicine and surgical subspecialties were preferred, students were not inclined towards primary care or diagnostic subspecialties. Incentives should be provided and other measures should be taken to make these branches more attractive.

Effect of tea phenolics and their aromatic fecal bacterial metabolites on intestinal microbiota.

Tea is rich in polyphenols and other phenolics that have been widely reported to have beneficial health effects. However, dietary polyphenols are not completely absorbed from the gastrointestinal tract and are metabolized by the gut microflora so that they and their metabolites may accumulate to exert physiological effects. In this study, we investigated the influence of the phenolic components of a tea extract and their aromatic metabolites upon bacterial growth. Fecal homogenates containing bacteria significantly catalyzed tea phenolics, including epicatechin, catechin, 3-O-methyl gallic acid, gallic acid and caffeic acid to generate aromatic metabolites dependent on bacterial species. Different strains of intestinal bacteria had varying degrees of growth sensitivity to tea phenolics and metabolites. Growth of certain pathogenic bacteria such as Clostridium perfringens, Clostridium difficile and Bacteroides spp. was significantly repressed by tea phenolics and their derivatives, while commensal anaerobes like Clostridium spp., Bifidobacterium spp. and probiotics such as Lactobacillus sp. were less severely affected. This indicates that tea phenolics exert significant effects on the intestinal environment by modulation of the intestinal bacterial population, probably by acting as metabolic prebiotics. Our observations provide further evidence for the importance of colonic bacteria in the metabolism, absorption and potential activity of phenolics in human health and disease. The bioactivity of different phenolics may play an important role in the maintenance of gastrointestinal health.

Human fecal water modifies adhesion of intestinal bacteria to Caco-2 cells.

The aqueous phase of feces (fecal water) has been suggested to mediate the effects of diet on colon carcinogenesis. We determined whether human fecal water samples, of varying genotoxic potential, had the capacity to alter adhesion of intestinal bacteria to intestinal (Caco-2) cells. Genotoxicity of fecal water samples was measured using the single-cell gel electrophoresis assay ("comet" assay), and bacterial adhesion was measured using a well-established model system. Fecal water genotoxicity was found to correlate positively with inhibition of adhesion of Escherichia coli strains, Salmonella species, and Enterococcus faecium to Caco-2 cells. The presence of fecal water samples did not interfere with adhesion of Bacteroides and Lactobacillus species. Inhibition of adhesion by fecal water was not due to cytotoxicity to Caco-2 cells as cytotoxicities of most fecal water samples were similar, nor was the inhibitory effect due to bacteriotoxicity as toxicity of fecal waters in the 10 strains of bacteria studied was not detected. Results indicate that components in fecal water may alter adhesion of intestinal bacteria to intestinal cell surfaces and that this effect may be correlated to the genotoxic potential of fecal water. This may have consequences for dietary effects on colon carcinogenesis.