Aliment Pharmacol Ther 2011; 34: 335–343
Summary
Background Treatment failure occurs in 20% of autoimmune hepatitis patients on prednisolone and azathioprine (AZA). There is no established second ...line treatment.
Aim To assess the efficacy of mycophenolate mofetil as second line treatment after AZA‐intolerance or AZA‐nonresponse in autoimmune hepatitis and overlap syndromes.
Methods Consecutive patients from the Dutch Autoimmune Hepatitis Group cohort, consisting of 661 patients, with autoimmune hepatitis or overlap syndromes, AZA‐intolerance or AZA‐nonresponse and past or present use of mycophenolate mofetil were included. Primary endpoint of mycophenolate mofetil treatment was biochemical remission. Secondary endpoints were biochemical response (without remission), treatment failure and prevention of disease progression.
Results Forty‐five patients treated with mycophenolate mofetil were included. In autoimmune hepatitis remission or response was achieved in 13% and 27% in the AZA‐nonresponse group compared to 67% and 0% in the AZA‐intolerance group (P = 0.008). In overlap‐syndromes remission or response was reached in 57% and 14% in the AZA‐nonresponse group and 63% and 25% of the AZA‐intolerance group (N.S.); 33% had side effects and 13% discontinued mycophenolate mofetil. Overall 38% had treatment failure; this was 60% in the autoimmune hepatitis AZA‐nonresponse group. Decompensated liver cirrhosis, liver transplantations and death were only seen in the autoimmune hepatitis AZA‐nonresponse group (P < 0.001).
Conclusions Mycophenolate mofetil induced response or remission in a majority of patients with autoimmune hepatitis and azathioprine‐intolerance and with overlap syndromes, irrespective of intolerance or nonresponse for azathioprine. In autoimmune hepatitis with azathioprine nonresponse mycophenolate mofetil is less often effective.
Background
This prospective multicentre study was performed to quantify the number of patients with minimal residual disease (ypT0–1) after neoadjuvant chemoradiotherapy and transanal endoscopic ...microsurgery (TEM) for rectal cancer.
Methods
Patients with clinically staged T1–3 N0 distal rectal cancer were treated with long‐course chemoradiotherapy. Clinical response was evaluated 6–8 weeks later and TEM performed. Total mesorectal excision was advocated in patients with residual disease (ypT2 or more).
Results
The clinical stage was cT1 N0 in ten patients, cT2 N0 in 29 and cT3 N0 in 16 patients. Chemoradiotherapy‐related complications of at least grade 3 occurred in 23 of 55 patients, with two deaths from toxicity, and two patients did not have TEM or major surgery. Among 47 patients who had TEM, ypT0–1 disease was found in 30, ypT0 N1 in one, ypT2 in 15 and ypT3 in one. Local recurrence developed in three of the nine patients with ypT2 tumours who declined further surgery. Postoperative complications grade I–IIIb occurred in 13 of 47 patients after TEM and in five of 12 after (completion) surgery. After a median follow‐up of 17 months, four local recurrences had developed overall, three in patients with ypT2 and one with ypT1 disease.
Conclusion
TEM after chemoradiotherapy enabled organ preservation in one‐half of the patients with rectal cancer.
Organ preservation feasible
Saccharomyces cerevisiae CEN.PK 113-7D is widely used for metabolic engineering and systems biology research in industry and academia. We sequenced, assembled, annotated and analyzed its genome. ...Single-nucleotide variations (SNV), insertions/deletions (indels) and differences in genome organization compared to the reference strain S. cerevisiae S288C were analyzed. In addition to a few large deletions and duplications, nearly 3000 indels were identified in the CEN.PK113-7D genome relative to S288C. These differences were overrepresented in genes whose functions are related to transcriptional regulation and chromatin remodelling. Some of these variations were caused by unstable tandem repeats, suggesting an innate evolvability of the corresponding genes. Besides a previously characterized mutation in adenylate cyclase, the CEN.PK113-7D genome sequence revealed a significant enrichment of non-synonymous mutations in genes encoding for components of the cAMP signalling pathway. Some phenotypic characteristics of the CEN.PK113-7D strains were explained by the presence of additional specific metabolic genes relative to S288C. In particular, the presence of the BIO1 and BIO6 genes correlated with a biotin prototrophy of CEN.PK113-7D. Furthermore, the copy number, chromosomal location and sequences of the MAL loci were resolved. The assembled sequence reveals that CEN.PK113-7D has a mosaic genome that combines characteristics of laboratory strains and wild-industrial strains.
Background
The standard surgical treatment for rectal cancer is total mesorectal excision (TME), which may negatively affect patients’ functional outcomes and quality of life (QoL). However, it is ...unclear how different TME techniques may impact patients’ functional outcomes and QoL. This systematic review and meta-analysis evaluated functional outcomes of urinary, sexual, and fecal functioning as well as QoL after open, laparoscopic (L-TME), robot-assisted (R-TME), and transanal total mesorectal excision (TaTME).
Methods
A systematic review and meta-analysis, based on the preferred reporting items for systematic reviews and meta-analysis statement, were conducted (PROSPERO: CRD42021240851). A literature review was performed (sources: PubMed, Medline, Embase, Scopus, Web of Science, and Cochrane Library databases; end-of-search date: September 1, 2023), and a quality assessment was performed using the Methodological index for non-randomized studies. A random-effects model was used to pool the data for the meta-analyses.
Results
Nineteen studies were included, reporting on 2495 patients (88 open, 1171 L-TME, 995 R-TME, and 241 TaTME). Quantitative analyses comparing L-TME vs. R-TME showed no significant differences regarding urinary and sexual functioning, except for urinary function at three months post-surgery, which favoured R-TME (SMD CI –0 .15 − 0.24 to − 0.06,
p
= 0.02;
n
= 401). Qualitative analyses identified most studies did not find significant differences in urinary, sexual, and fecal functioning and QoL between different techniques.
Conclusions
This systematic review and meta-analysis highlight a significant gap in the literature concerning the evaluation of functional outcomes and QoL after TME for rectal cancer treatment. This study emphasizes the need for high-quality, randomized-controlled, and prospective cohort studies evaluating these outcomes. Based on the limited available evidence, this systematic review and meta-analysis suggests no significant differences in patients' urinary, sexual, and fecal functioning and their QoL across various TME techniques.
Lager brewing strains of Saccharomyces pastorianus are natural interspecific hybrids originating from the spontaneous hybridization of Saccharomyces cerevisiae and Saccharomyces eubayanus. Over the ...past 500 years, S. pastorianus has been domesticated to become one of the most important industrial microorganisms. Production of lager-type beers requires a set of essential phenotypes, including the ability to ferment maltose and maltotriose at low temperature, the production of flavors and aromas, and the ability to flocculate. Understanding of the molecular basis of complex brewing-related phenotypic traits is a prerequisite for rational strain improvement. While genome sequences have been reported, the variability and dynamics of S. pastorianus genomes have not been investigated in detail. Here, using deep sequencing and chromosome copy number analysis, we showed that S. pastorianus strain CBS1483 exhibited extensive aneuploidy. This was confirmed by quantitative PCR and by flow cytometry. As a direct consequence of this aneuploidy, a massive number of sequence variants was identified, leading to at least 1,800 additional protein variants in S. pastorianus CBS1483. Analysis of eight additional S. pastorianus strains revealed that the previously defined group I strains showed comparable karyotypes, while group II strains showed large interstrain karyotypic variability. Comparison of three strains with nearly identical genome sequences revealed substantial chromosome copy number variation, which may contribute to strain-specific phenotypic traits. The observed variability of lager yeast genomes demonstrates that systematic linking of genotype to phenotype requires a three-dimensional genome analysis encompassing physical chromosomal structures, the copy number of individual chromosomes or chromosomal regions, and the allelic variation of copies of individual genes.
The heterotrophic marine microalga Crypthecodinium cohnii produces docosahexaenoic acid (DHA), a polyunsaturated fatty acid with food and pharmaceutical applications. So far, DHA production has been ...studied with glucose and acetic acid as carbon sources. This study investigates the potential of ethanol as an alternative carbon source for DHA production by C. cohnii. In shake-flask cultures, the alga was able to grow on ethanol. The specific growth rate was optimal with 5 g l-1 ethanol and growth did not occur at 0 g l-1 and above 15 g l-1. By contrast, in fed-batch cultivations with a controlled feed of pure ethanol, cumulative ethanol addition could be much higher than 15 g l-1, thus enabling a high final cell density and DHA production. In a representative fed-batch cultivation of C. cohnii with pure ethanol as feed, 83 g dry biomass l-1, 35 g total lipid l-1 and 11.7 g DHA l-1 were produced in 220 h. The overall volumetric productivity of DHA was 53 mg l-1 h-1, which is the highest value reported so far for this alga.
Profiles of genome-wide transcriptional events for a given environmental condition can be of importance in the diagnosis of
poorly defined environments. To identify clusters of genes constituting ...such diagnostic profiles, we characterized the specific
transcriptional responses of Saccharomyces cerevisiae to growth limitation by carbon, nitrogen, phosphorus, or sulfur. Microarray experiments were performed using cells growing
in steady-state conditions in chemostat cultures at the same dilution rate. This enabled us to study the effects of one particular
limitation while other growth parameters (pH, temperature, dissolved oxygen tension) remained constant. Furthermore, the composition
of the media fed to the cultures was altered so that the concentrations of excess nutrients were comparable between experimental
conditions. In total, 1881 transcripts (31% of the annotated genome) were significantly changed between at least two growth
conditions. Of those, 484 were significantly higher or lower in one limitation only. The functional annotations of these genes
indicated cellular metabolism was altered to meet the growth requirements for nutrient-limited growth. Furthermore, we identified
responses for several active transcription factors with a role in nutrient assimilation. Finally, 51 genes were identified
that showed 10-fold higher or lower expression in a single condition only. The transcription of these genes can be used as
indicators for the characterization of nutrient-limited growth conditions and provide information for metabolic engineering
strategies.
A quantitative analysis of the impact of feedback inhibition on aromatic amino acid biosynthesis was performed in chemostat cultures of
Saccharomyces cerevisiae. Introduction of a ...tyrosine-insensitive allele of
ARO4 (encoding 3-deoxy-
d-
arabino-heptulosonate-7-phosphate synthase) caused a three-fold increase of intracellular phenylalanine and tyrosine concentrations. These amino acids were not detected extracellularly. However, an over 100-fold increase of the extracellular levels of phenylacetate, phenylethanol and their para-hydroxyl analogues was observed. The total increase of the flux through the aromatic pathway was estimated to be over four-fold. Individual overexpression of either the wild-type or feedback insensitive allele of
ARO7 (encoding chorismate mutase had no significant impact. However when they were combined with the Tyr-insensitive
ARO4 allele in combination with the Tyr-insensitive
ARO4 allele, extracellular concentrations of aromatic compounds were increased by over 200-fold relative to the reference strain, corresponding to a 4.5-fold increase of the flux through the aromatic amino acid biosynthesis pathway. Elimination of allosteric control on these two key reactions in aromatic amino acid metabolism significantly affected intracellular concentrations of several non-aromatic amino acids. This broader impact of amino acid biosynthesis presents a challenge in rational optimization of the production of specific amino acids and derived flavour compounds.
The specific growth rate is a key control parameter in the industrial production of baker's yeast. Nevertheless, quantitative data describing its effect on fermentative capacity are not available ...from the literature. In this study, the effect of the specific growth rate on the physiology and fermentative capacity of an industrial Saccharomyces cerevisiae strain in aerobic, glucose-limited chemostat cultures was investigated. At specific growth rates (dilution rates, D) below 0.23 h-1, glucose metabolism was fully respiratory. Above this dilution rate, respirofementative metabolism set in, with ethanol production rates of up to 14 mmol of ethanol (.) g of biomass-1 (.) h-1 at D = 0.40 h-1. A substantial fermentative capacity (assayed offline as ethanol production rate under anaerobic conditions) was found in cultures in which no ethanol was detectable (D 0.28 h-1). This fermentative capacity increased with increasing dilution rates, from 10.0 mmol of ethanol (.) g of dry yeast biomass-1 (.) h-1 atD
In contrast to batch cultivation, chemostat cultivation allows the identification of carbon source responses without interference by carbon-catabolite repression, accumulation of toxic products, and ...differences in specific growth rate. This study focuses on the yeast Saccharomyces cerevisiae, grown in aerobic, carbon-limited chemostat cultures. Genome-wide transcript levels and in vivo fluxes were compared for growth on two sugars, glucose and maltose, and for two C2-compounds, ethanol and acetate. In contrast to previous reports on batch cultures, few genes (180 genes) responded to changes of the carbon source by a changed transcript level. Very few transcript levels were changed when glucose as the growth-limiting nutrient was compared with maltose (33 transcripts), or when acetate was compared with ethanol (16 transcripts). Although metabolic flux analysis using a stoichiometric model revealed major changes in the central carbon metabolism, only 117 genes exhibited a significantly different transcript level when sugars and C2-compounds were provided as the growth-limiting nutrient. Despite the extensive knowledge on carbon source regulation in yeast, many of the carbon source-responsive genes encoded proteins with unknown or incompletely characterized biological functions. In silico promoter analysis of carbon source-responsive genes confirmed the involvement of several known transcriptional regulators and suggested the involvement of additional regulators. Transcripts involved in the glyoxylate cycle and gluconeogenesis showed a good correlation with in vivo fluxes. This correlation was, however, not observed for other important pathways, including the pentose-phosphate pathway, tricarboxylic acid cycle, and, in particular, glycolysis. These results indicate that in vivo fluxes in the central carbon metabolism of S. cerevisiae grown in steadystate, carbon-limited chemostat cultures are controlled to a large extent via post-transcriptional mechanisms.
PDF
