The effect of carbohydrate sources: Sucrose, invert sugar and components of manuka honey, on core bacteria in the digestive tract of adult honey bees (Apis mellifera).

Bacteria within the digestive tract of adult honey bees are likely to play a key role in the digestion of sugar-rich foods. However, the influence of diet on honey bee gut bacteria is not well understood. During periods of low floral abundance, beekeepers often supplement the natural sources of carbohydrate that honey bees collect, such as nectar, with various forms of carbohydrates such as sucrose (a disaccharide) and invert sugar (a mixture of the monosaccharides glucose and fructose). We compared the effect of these sugar supplements on the relative abundance of bacteria in the gut of bees by feeding bees from a single colony, two natural diets: manuka honey, a monofloral honey with known antibacterial properties, and a hive diet; and artificial diets of invert sugar, sucrose solution, and sucrose solutions containing synthesised compounds associated with the antibacterial properties of manuka honey. 16S ribosomal RNA (rRNA)-based sequencing showed that dietary regimes containing manuka honey, sucrose and invert sugar did not alter the relative abundance of dominant core bacteria after 6 days of being fed these diets. However, sucrose-rich diets increased the relative abundances of three sub-dominant core bacteria, Rhizobiaceae, Acetobacteraceae, and Lactobacillus kunkeei, and decreased the relative abundance of Frischella perrara, all which significantly altered the bacterial composition. Acetogenic bacteria from the Rhizobiaceae and Acetobacteraceae families increased two- to five-fold when bees were fed sucrose. These results suggest that sucrose fuels the proliferation of specific low abundance primary sucrose-feeders, which metabolise sugars into monosaccharides, and then to acetate.

In adults with osteoarthritis of the knee, is conservative management more effective than intra-articular corticosteroid injections in relieving pain?

CLINICAL QUESTION: In adults with osteoarthritis of the knee, do conservative management methods such as weight reduction, physical therapy, Tai Chi, non-steroidal anti-inflammatory drugs (NSAIDs), and others provide more and longer pain relief and functionality of the knee, as well as overall well-being, when compared to corticosteroid knee injections? ANSWER: Yes. Although there are limited head-to-head trials directly comparing each alternative method to corticosteroid injections, overall evidence appears to indicate conservative methods as being more effective than injections, especially when considering long-term pain relief and functionality.

Transcriptomic analysis of degraded forensic body fluids.

Massively parallel sequencing (MPS) has facilitated a significant increase in transcriptomic studies in all biological disciplines. However, the analysis of degraded RNA remains a genuine challenge in practice. In forensic science the biological samples encountered are often extensively degraded and of low abundance. RNA from these compromised samples is used for body fluid identification through the detection of body fluid-specific transcripts. Here we demonstrate the sequencing of four forensically relevant body fluids: oral mucosa/saliva (buccal), circulatory blood, menstrual blood and vaginal fluid. RNA was extracted from fresh, two and six week aged samples. Despite the extensive degradation of most body fluids, significant high quality sequencing output (>80% sequence above Q30) was generated. An average of over 80% of reads from all but one sample aligned successfully to the reference human genome. Furthermore, FPKMs (fragments per kilobase of exon per million fragments mapped) generated indicate the accurate detection of known body fluid markers in respective body fluids. Assessment of global gene expression levels over degradation time enabled the characterisation of differential RNA degradation in different body fluids. This study demonstrates the practical application of MPS technology for the accurate analysis of degraded RNA from minimal samples.

Role of recurrent hypoxia-ischemia in preterm white matter injury severity.

OBJECTIVE: Although the spectrum of white matter injury (WMI) in preterm infants is shifting from cystic necrotic lesions to milder forms, the factors that contribute to this changing spectrum are unclear. We hypothesized that recurrent hypoxia-ischemia (rHI) will exacerbate the spectrum of WMI defined by markers of inflammation and molecules related to the extracellular matrix (hyaluronan (HA) and the PH20 hyaluronidase) that regulate maturation of the oligodendrocyte (OL) lineage after WMI. METHODS: We employed a preterm fetal sheep model of in utero moderate hypoxemia and global severe but not complete cerebral ischemia that reproduces the spectrum of human WMI. The response to rHI was compared against corresponding early or later single episodes of HI. An ordinal rating scale of WMI was compared against an unbiased quantitative image analysis protocol that provided continuous histo-pathological outcome measures for astrogliosis and microglial activation. Late oligodendrocyte progenitors (preOLs) were quantified by stereology. Analysis of hyaluronan and the hyaluronidase PH20 defined the progressive response of the extracellular matrix to WMI. RESULTS: rHI resulted in a more severe spectrum of WMI with a greater burden of necrosis, but an expanded population of preOLs that displayed reduced susceptibility to cell death. WMI from single episodes of HI or rHI was accompanied by elevated HA levels and increased labeling for PH20. Expression of PH20 in fetal ovine WMI was confirmed by RT-PCR and RNA-sequencing. CONCLUSIONS: rHI is associated with an increased risk for more severe WMI with necrosis, but reduced risk for preOL degeneration compared to single episodes of HI. Expansion of the preOL pool may be linked to elevated hyaluronan and PH20.

In vitro grown pollen tubes of Nicotiana alata actively synthesise a fucosylated xyloglucan.

Nicotiana alata pollen tubes are a widely used model for studies of polarized tip growth and cell wall synthesis in plants. To better understand these processes, RNA-Seq and de novo assembly methods were used to produce a transcriptome of N. alata pollen grains. Notable in the reconstructed transcriptome were sequences encoding proteins that are involved in the synthesis and remodelling of xyloglucan, a cell wall polysaccharide previously not thought to be deposited in Nicotiana pollen tube walls. Expression of several xyloglucan-related genes in actively growing pollen tubes was confirmed and xyloglucan epitopes were detected in the wall with carbohydrate-specific antibodies: the major xyloglucan oligosaccharides found in N. alata pollen grains and tubes were fucosylated, an unusual structure for the Solanaceae, the family to which Nicotiana belongs. Finally, carbohydrate linkages consistent with xyloglucan were identified chemically in the walls of N. alata pollen grains and pollen tubes grown in culture. The presence of a fucosylated xyloglucan in Nicotiana pollen tube walls was thus confirmed. The consequences of this discovery to models of pollen tube growth dynamics and more generally to polarised tip-growing cells in plants are discussed.

Intraparenchymal metastases to the spleen from ovarian cancer: a case report.

INTRODUCTION: Splenic tumors are rare and present a diagnostic dilemma. Metastatic carcinoma to the spleen is unusual. Visceral metastases in patients with ovarian cancer represent hematogenous spread of the disease; capsular involvement resulting from serosal and peritoneal seeding is more common. We present a patient with intraparenchymal splenic metastasis from ovarian carcinoma. This case demonstrates a rare etiology of an intraparenchymal solid splenic mass. CASE PRESENTATION: An 85-year-old woman presented with left upper quadrant pain. During her evaluation, a computed tomography scan revealed intraparenchymal splenic masses. An elective splenectomy was performed, during which ovarian cancer, which had not been revealed by the pre-operative computed tomography, was detected. There was no involvement of the splenic capsule by direct extension of the tumor, as is usually the case for ovarian cancer, but only intraparenchymal metastases. This mode of metastasis to the spleen has been described but is quite rare, and ovarian cancer presenting as a splenic mass is even more so. CONCLUSION: Splenic metastasis is a relatively rare event. It is often asymptomatic and is usually detected as part of multiorgan metastases. Symptomatic cases, though rare, do occur, and as in our patient, a thorough clinical evaluation is important to help direct the treatment plan. This case is a reminder to be cognizant of one of the less likely differential diagnoses of an intraparenchymal solid splenic mass.