Species-wide quantitative transcriptomes and proteomes reveal distinct genetic control of gene expression variation in yeast.

Gene expression varies between individuals and corresponds to a key step linking genotypes to phenotypes. However, our knowledge regarding the species-wide genetic control of protein abundance, including its dependency on transcript levels, is very limited. Here, we have determined quantitative proteomes of a large population of 942 diverse natural Saccharomyces cerevisiae yeast isolates. We found that mRNA and protein abundances are weakly correlated at the population gene level. While the protein co-expression network recapitulates major biological functions, differential expression patterns reveal proteomic signatures related to specific populations. Comprehensive genetic association analyses highlight that genetic variants associated with variation in protein (pQTL) and transcript (eQTL) levels poorly overlap (3.6%). Our results demonstrate that transcriptome and proteome are governed by distinct genetic bases, likely explained by protein turnover. It also highlights the importance of integrating these different levels of gene expression to better understand the genotype-phenotype relationship. Highlights: At the level of individual genes, the abundance of transcripts and proteins is weakly correlated within a species ( ρ = 0.165). While the proteome is not imprinted by population structure, co-expression patterns recapitulate the cellular functional landscapeWild populations exhibit a higher abundance of respiration-related proteins compared to domesticated populationsLoci that influence protein abundance differ from those that impact transcript levels, likely because of protein turnover.

Seasonality of spina bifida in Northern Germany.

PURPOSE: To verify a seasonal variation in the incidence of spina bifida and thus to identify possible environmental triggers leading to its developement. METHODS: An interdisciplinary approach has been taken to develop a better understanding of spina bifida through collaborative efforts from investigators specializing in genetics, fetal pathology, paediatrics, neuro-surgery and prenatal ultrasonographic diagnosis. All pregnancies with fetal spina bifida were retrospectively analyzed from May 1 1993 through May 1 2010 at Luebeck University Fetal Health Center. Results were used to construct a model to predict the occurrence of fetal spina bifida based on seasonal variation and environmental influence reflected by climatic changes and environmental pollution. Furthermore, data were categorized in respect to the date of conception and subdivided into date of conception during summer (April-September) and winter months (October-March). RESULTS: Neither a seasonal distribution of conception for fetuses with spina bifida in the defined time frame could be verified nor a relevant influence of the analyzed environmental factors on the prevalence of spina bifida could be proved. The incidence of spina bifida has remained relatively stable within the last 17 years at 2.5 per 1,000 screened pregnancies. CONCLUSION: Since we were unable to demonstrate a relationship between seasonal variation and certain environmental factors on the incidence of fetal spina bifida, other factors should be investigated for a possible association with the onset of fetal spina bifida.

Teenage deliveries in Northern Germany: always a risk factor for higher surgical delivery rates?

PURPOSE: To evaluate the impact of young maternal age on labour, intrapartum assessment and delivery mode. METHODS: A retrospective cohort analysis was conducted of 13,941 deliveries at a tertiary delivery unit between 2000 and 2009. Patients aged less than 18 years were compared with patients aged 18 years or older. The main outcome was defined as mode of delivery. Frequencies and odds ratios for adverse maternal-foetal outcomes were calculated for primiparous women. RESULTS: Of the deliveries occurring during the study period, 6,863 (49.2%) met the inclusion criteria. A total of 156 deliveries (2.3%) occurred among teenagers less than 18 years and 6,707 among patients 18 years and older. Compared with patients 18 years of age and older, younger maternal age was associated with a higher chance of spontaneous delivery [adjusted odds ratio (OR) 2.07, 95% confidence interval (CI) 1.45-2.93] than via operation (vaginal operative delivery: OR 0.98, 95% CI 0.48-2.03; secondary caesarean delivery: adjusted OR 0.51, 95% CI 0.32-0.82). CONCLUSION: Young maternal age at delivery does not represent a risk factor for high surgical delivery rates.

Predicting visual outcome after macular hole surgery using scanning laser ophthalmoscope microperimetry.

AIMS: To determine if postoperative visual outcome after successful macular hole surgery can be predicted with preoperative scanning laser ophthalmoscope (SLO) microperimetry. METHODS: A prospective non-comparative study of 16 eyes in 15 patients examined before the surgery. RESULTS: Visual outcome following macular hole surgery correlated with the "maximum parahole sensitivity", the highest intensity of stimulus to which the patient did not respond to any of the stimuli around the hole. Preoperative visual acuity, duration of the symptoms, size of the macular hole, and the "minimum parahole sensitivity", the lowest intensity to which the patient responded to all the stimuli around the hole, did not correlate significantly with postoperative visual acuity. CONCLUSION: Preoperative assessment of patients using SLO microperimetry is a good predictor of visual outcome after macular hole surgery.

Vitreous surgery for traumatic macular holes.

PURPOSE: To review the anatomic and visual outcomes of a series of patients with traumatic macular holes who underwent vitreous surgery without adjunctive therapy. METHODS: We performed a retrospective chart review of 23 patients who underwent vitrectomy, fluid-gas exchange, and sulfur hexafluoride gas tamponade for traumatic macular holes. Anatomic success rate and final visual improvement after the surgery were studied. RESULTS: Medical records of 23 patients (23 eyes) who underwent this procedure were reviewed. Closure of the macular hole was achieved in 16 (70%) eyes with one surgery and in 22 (96%) of the 23 eyes with two surgeries. The mean best-corrected preoperative visual acuity was 20/160, and postoperative visual acuity was 20/60 with a mean (+/- standard deviation) follow-up of 23+/-13 months (range 3-56 months). Fourteen (61 %) of the 23 eyes achieved a best-corrected postoperative visual acuity of 20/60 or better, and 11 (48%) of the 23 eyes achieved 20/40 or better. Twenty (87%) of the 23 eyes achieved at least two lines of visual improvement. CONCLUSIONS: Vitreous surgery without adjunctive therapy for traumatic macular holes can lead to anatomic success and visual acuity improvement in most eyes.

Electron microscopic immunohistochemistry of ocular and extraocular pseudoexfoliative material.

To investigate the nature of extraocular pseudoexfoliative (PSX) material, and to validate the hypothesis that the PSX syndrome is a systemic disorder, we studied the immunoreactivity of intraocular and extraocular PSX material from patients with the PSX syndrome using antibodies against proteins of extracellular matrices. Surgical specimens of four different tissues were obtained from human eyes with the PSX syndrome: nine trabecular tissues, three cataractous lenses, six bulbar conjunctivas, and seven lid skins. These tissues were processed for electron microscopic immunohistochemistry, and stained with antibodies against vitronectin, fibronectin, laminin, and elastin, by an indirect immunogold procedure. Density of the gold particles located on the PSX material was estimated by video image analysis. Statistical analysis of the data revealed that the PSX material from trabecular tissues, lenses, bulbar conjunctivas, and lid skins had almost identical immunoreactivity to the antibodies studied. PSX materials of trabecular tissues, lenses, bulbar conjunctivas, and lid skins were found to have not only a similar ultrastructure, but also almost identical immunohistochemical characteristics. These results support the hypothesis that the PSX syndrome is a systemic disorder.

Electron microscopic lectin histochemistry of the trabecular meshworks in human eyes.

Ten normal human trabecular meshworks were examined by electron microscopy using avidin-biotin complex in order to investigate the localization of binding sites of eight lectins. The tissue specimens were fixed in paraformaldehyde and glutaraldehyde mixture and embedded in Lowicryl K4M at low temperature. The ultrathin sections were stained with biotin labelled lectins and colloidal gold labelled streptoavidin and were observed with the conventional transmission electron microscope. Some lectins such as ABA, ConA and DSA were localized on fine fibrils underneath the endothelium of the trabecular wall of the Schlemm's canal, electron-dense cores of elastic fibers, fine granular like materials, basement membranes, collagen fibers and the long-spacing fibers. However, the other lectins such as DBA, SBA, Lotus, UEA-I and RCA60 were not specifically localized in these tissues. From the results it was demonstrated that the differential ultrastructural localization of glycoconjugate residues in the human trabecular meshworks can be revealed using this lectin staining.

Lectin electron microscopic histochemistry of the pseudoexfoliative material in the skin.

PURPOSE: To investigate the hypothesis that pseudoexfoliation (PSX) syndrome is a systemic disorder, the authors studied the composition of glycoconjugates in the intraocular and extraocular PSX material at the electron microscopic level, using a panel of lectins as cytochemical probes. METHODS: The authors examined 8 lid skins, 11 trabecular tissues, and 3 cataractous lenses from human eyes with PSX syndrome. Tissues were processed for electron microscopical histochemistry and stained with PNA, RCA120, DBA, SBA, ConA, WGA, UEA-I, and Lotus, with an indirect lectin-colloidal gold technique. RESULTS: Both the intraocular and extraocular PSX materials manifested almost identical reactivity to lectins, which indicated that glycoconjugates in the PSX material contained with sugar residues of galactose (PNA, RCA120), alpha-mannose (ConA), and N-acetyl-D-glucosamine (WGA). On the other hand, it was indicated that sugar residues of N-acetyl-D-galactosamine (DBA, SBA) and fucose (UEA-I, Lotus) were absent. Granular inclusions and microfibrils in the capsule and ocular zonules were stained similarly and weakly. CONCLUSIONS: The intraocular and extraocular PSX materials contained the same sugar residues of glycoconjugates, which suggested that those materials had the same nature. This study, the first documentation of lectin-binding sites on the extraocular PSX material, supported the hypothesis of PSX syndrome as a systemic disorder.

Lens coloboma and Alport-like glomerulonephritis.

An unusual case of bilateral lens coloboma and Alport-like glomerulonephritis is reported. In a 12-year-old boy and in several family members; Alport-like glomerulonephritis was diagnosed without deafness and without ocular signs of Alport syndrome. A bilateral lens coloboma however was observed in the propositus. To our knowledge this is the first reported case of lens coloboma with Alport-like glomerulonephritis.

[Lectin electron histochemistry in the skin in patients with exfoliation syndrome].

Exfoliation syndrome has recently been suggested to have a more widespread distribution from the findings of exfoliative-like material outside the globe. To determine whether exfoliative-like material and exfoliative material are identical, they were characterized by electron microscopic lectin histochemistry using sixteen kinds of lectin; PNA, RCA60 and 120, ABA, DBA, SBA, ConA, LCA, WGA, DSA, PHA-E4 and L4, UEA-I, Lotus, MAM and SSA. The staining pattern indicated that sugar residues in these two materials on the trabecular meshwork, lens, and skin have the same characteristics, containing glycoconjugates with sugar residues of beta-galactosyl, alpha-mannosyl, N-acetyl-D-glucosaminyl, and terminal sialic acid.

[Lectin electron microscopic histochemistry of exfoliative material from capsular glaucoma].

Exfoliative material of capsular glaucoma was studied by electron microscopic lectin histochemistry using sixteen kinds of lectin; PNA, RCA60 and 120, ABA, DBA, SBA, ConA, LCA, WGA, DSA, PHA-E4 and L4, UEA-I, Lotus, MAM, and SSA. The results indicated that sugar residues in exfoliative material on the lens and trabecular meshwork have the same characteristics, i.e., they contain glycoconjugates with sugar residues of beta-galactosyl, alpha-mannosyl, N-acetyl-D-glucosaminyl, and terminal sialic acid. The lectin staining pattern of microfibrils in exfoliative material, radially oriented fibrils and linear densities in the lens capsule, and zonular lamella was also similar to that of exfoliative material, and suggested their close association with exfoliative material. These results also indicated that lectin can be employed in the detection and identification of exfoliative material in various tissues.

Analysis and bioequivalency study on two tablet formulations of co-trimoxazole.

This paper describes an analytical procedure for simultaneous quantification of trimethoprim (TMP) and sulphamethoxazole (SMZ) in serum. Serum samples were rendered alkaline with glycine-sodium hydroxide buffer (pH 9.1) and extracted with ethyl acetate. The reconstituted sample was analysed using reversed-phase C-18 column high-performance chromatography. The mobile phase consisted of 75% triethyl ammonium acetate buffer, 20% methanol and 5% acetonitrile. The analytes were monitored at 289 nm and tetroxoprim was used as an internal standard. The maximum values for intra-day coefficients of variation (CV) for TMP-and SMZ were 5.7 and 2.1%, respectively. Interday CV values were 6.4 and 2.2%, respectively. The method was used to compare the bioavailability of two tablet formulations in terms of their pharmacokinetic parameters following oral administration of the tablets to 18 volunteers.