Complement component 4A protein levels are negatively related to frontal volumes in patients with schizophrenia spectrum disorders

BACKGROUND

Excessive C4A-gene expression may result in increased microglia-mediated synaptic pruning. As C4A overexpression is observed in schizophrenia spectrum disorders (SSD), this mechanism may account for the altered brain morphology (i.e. reduced volume and cortical thickness) and cognitive symptoms that characterize SSD. Therefore, this study investigates the association of C4A serum protein levels with brain morphology and cognition, and in particular whether this association differs between recent-onset SSD (n = 69) and HC (n = 40).

METHODS

Serum C4A protein levels were compared between groups. Main outcomes included total gray matter volume, mean cortical thickness and cognitive performance. Regression analysis on these outcomes included C4A level, group (SSD vs. HC), and C4A*Group interactions. All statistical tests were corrected for age, sex, BMI, and antipsychotic medication dose. Follow-up analyses were performed on separate brain regions and scores on cognitive sub-tasks.

RESULTS

The group difference in C4A levels was not statistically significant (p = 0.86). The main outcomes did not show a significant interaction effect (p > 0.13) or a C4A main effect (p > 0.27). Follow-up analyses revealed significant interaction effects for the left medial orbitofrontal and left frontal pole volumes (p < 0.001): C4A was negatively related to these volumes in SSD, but positively in HC.

CONCLUSION

This study demonstrated that C4A was negatively related to - specifically - frontal brain volumes in SSD, but this relation was inverse for HC. The results support the hypothesis of complement-mediated brain volume reduction in SSD. The results also suggest that C4A has a differential association with brain morphology in SSD compared to HC.

Imaging features of COVID-19-associated secondary sclerosing cholangitis on magnetic resonance cholangiopancreatography: a retrospective analysis

Background

Despite emerging reports of secondary sclerosing cholangitis (SSC) in critically ill COVID-19 patients little is known about its imaging findings. It presents as delayed progressive cholestatic liver injury with risk of progression to cirrhosis. Diagnosis cannot be made based on clinical presentation and laboratory markers alone. Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) can aid in the diagnosis. The aim of this study was to describe MRI/MRCP imaging features of COVID-19-associated SSC.

Results

Seventeen patients (mean age 60.5 years, 15 male) who underwent MRI/MRCP were included. All had been admitted to intensive care unit (ICU) (median duration of ICU stay 10 weeks, range, 2–28 weeks) and developed acute respiratory distress syndrome requiring mechanical ventilation. On imaging, all patients had intrahepatic bile duct strictures and 10 (58.8%) had associated upstream dilatation. Intrahepatic bile duct beading was seen in 14 cases (82.3%). Only one patient (5.9%) had extrahepatic bile duct stricturing. Patchy arterial phase hyperenhancement and high signal on T2- and diffusion-weighted images were seen in 7 cases (53.8%) and 9 cases (52.9%), respectively. Biliary casts were seen in 2 cases (11.8%). Periportal lymphadenopathy and vascular complications were not seen.

Conclusion

On MRI/MRCP, COVID-19-associated SSC presents with multiple intrahepatic bile duct strictures with or without upstream dilatation and intrahepatic bile duct beading. Surrounding hepatic parenchymal changes including alterations in enhancement and T2 signal are common. The extrahepatic biliary tree was typically spared and periportal lymphadenopathy was missing in all patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-022-01266-9.

Immune cell infiltration in colonic cancer: correlation between biopsy and surgical specimens

Infiltration of CD3+ and CD8+ T cells in tumour biopsies of patients with colonic cancer correlated positively with CD3+ and CD8+ T cell infiltration in matched tumour surgical specimens. This opens new perspectives in the potential of tumour biopsies for prognosis and treatment decisions.

Spiral breast computed tomography (CT): signal-to-noise and dose optimization using 3D-printed phantoms

Objectives

To investigate the dependence of signal-to-noise ratio (SNR) and calculated average dose per volume of spiral breast-CT (B-CT) on breast size and breast density and to provide a guideline for choosing the optimal tube current for each B-CT examination.

Materials and methods

Three representative B-CT datasets (small, medium, large breast size) were chosen to create 3D-printed breast phantoms. The phantoms were filled with four different agarose-oil-emulsions mimicking differences in breast densities. Phantoms were scanned in a B-CT system with systematic variation of the tube current (6, 12.5, 25, 32, 40, 50, 64, 80, 100, 125 mA). Evaluation of SNR and the average dose per volume using Monte Carlo simulations were performed for high (HR) and standard (STD) spatial resolution.

Results

SNR and average dose per volume increased with increasing tube current. Artifacts had negligible influence on image evaluation. SNR values ≥ 35 (HR) and ≥ 100 (STD) offer sufficient image quality for clinical evaluation with SNR being more dependent on breast density than on breast size. For an average absorbed dose limit of 6.5 mGy for the medium and large phantoms and 7 mGy for the small phantom, optimal tube currents were either 25 or 32 mA.

Conclusions

B-CT offers the possibility to vary the X-ray tube current, allowing image quality optimization based on individual patient’s characteristics such as breast size and density. This study describes the optimal B-CT acquisition parameters, which provide diagnostic image quality for various breast sizes and densities, while keeping the average dose at a level similar to digital mammography.

Key Points

• Image quality optimization based on breast size and density varying the tube current using spiral B-CT.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-020-07549-3.

Proton-electron mass ratio from laser spectroscopy of HD+ at the part-per-trillion level

Recent mass measurements of light atomic nuclei in Penning traps have indicated possible inconsistencies in closely related physical constants such as the proton-electron and deuteron-proton mass ratios. These quantities also influence the predicted vibrational spectrum of the deuterated molecular hydrogen ion (HD+) in its electronic ground state. We used Doppler-free two-photon laser spectroscopy to measure the frequency of the v = 0→9 overtone transition (v, vibrational quantum number) of this spectrum with an uncertainty of 2.9 parts per trillion. By leveraging high-precision ab initio calculations, we converted our measurement to tight constraints on the proton-electron and deuteron-proton mass ratios, consistent with the most recent Penning trap determinations of these quantities. This results in a precision of 21 parts per trillion for the value of the proton-electron mass ratio.

Is there evidence for more than two diffusion components in abdominal organs? - A magnetic resonance imaging study in healthy volunteers

The most commonly applied model for the description of diffusion-weighted imaging (DWI) data in perfused organs is bicompartmental intravoxel incoherent motion (IVIM) analysis. In this study, we assessed the ground truth of underlying diffusion components in healthy abdominal organs using an extensive DWI protocol and subsequent computation of apparent diffusion coefficient 'spectra', similar to the computation of previously described T₂ relaxation spectra. Diffusion datasets of eight healthy subjects were acquired in a 3-T magnetic resonance scanner using 68 different b values during free breathing (equidistantly placed in the range 0-1005 s/mm² ). Signal intensity curves as a function of the b value were analyzed in liver, spleen and kidneys using non-negative least-squares fitting to a distribution of decaying exponential functions with minimum amplitude energy regularization. In all assessed organs, the typical slow- and fast-diffusing components of the IVIM model were detected [liver: true diffusion D = (1.26 ± 0.01) × 10^-3 mm² /s, pseudodiffusion D* = (270 ± 44) × 10^-3 mm² /s; kidney cortex: D = (2.26 ± 0.07) × 10^-3 mm² /s, D* = (264 ± 78) × 10^-3 mm² /s; kidney medulla: D = (1.57 ± 0.28) × 10^-3 mm² /s, D* = (168 ± 18) × 10^-3 mm² /s; spleen: D = (0.91 ± 0.01) × 10^-3 mm² /s, D* = (69.8 ± 0.50) × 10^-3 mm² /s]. However, in the liver and kidney, a third component between D and D* was found [liver: D' = (43.8 ± 5.9) × 10^-3 mm² /s; kidney cortex: D' = (23.8 ± 11.5) × 10^-3 mm² /s; kidney medulla: D' = (5.23 ± 0.93) × 10^-3 mm² /s], whereas no third component was detected in the spleen. Fitting with a diffusion kurtosis model did not lead to a better fit of the resulting curves to the acquired data compared with apparent diffusion coefficient spectrum analysis. For a most accurate description of diffusion properties in the liver and the kidneys, a more sophisticated model seems to be required including three diffusion components.

Intestinal-specific activatable Myb initiates colon tumorigenesis in mice

Transcription factor Myb is overexpressed in most colorectal cancers (CRC). Patients with CRC expressing the highest Myb are more likely to relapse. We previously showed that mono-allelic loss of Myb in an Adenomatous polyposis coli (APC)-driven CRC mouse model (Apc^Min/+) significantly improves survival. Here we directly investigated the association of Myb with poor prognosis and how Myb co-operates with tumor suppressor genes (TSGs) (Apc) and cell cycle regulator, p27. Here we generated the first intestinal-specific, inducible transgenic model; a MybER transgene encoding a tamoxifen-inducible fusion protein between Myb and the estrogen receptor-α ligand-binding domain driven by the intestinal-specific promoter, Gpa33. This was to mimic human CRC with constitutive Myb activity in a highly tractable mouse model. We confirmed that the transgene was faithfully expressed and inducible in intestinal stem cells (ISCs) before embarking on carcinogenesis studies. Activation of the MybER did not change colon homeostasis unless one p27 allele was lost. We then established that MybER activation during CRC initiation using a pro-carcinogen treatment, azoxymethane (AOM), augmented most measured aspects of ISC gene expression and function and accelerated tumorigenesis in mice. CRC-associated symptoms of patients including intestinal bleeding and anaemia were faithfully mimicked in AOM-treated MybER transgenic mice and implicated hypoxia and vessel leakage identifying an additional pathogenic role for Myb. Collectively, the results suggest that Myb expands the ISC pool within which CRC is initiated while co-operating with TSG loss. Myb further exacerbates CRC pathology partly explaining why high MYB is a predictor of worse patient outcome.

Different surgical approaches for stress urinary incontinence in women

Stress urinary incontinence (SUI) constitutes involuntary voiding as a consequence of rising intra-abdominal pressure caused by sphincter weakness. In recent years studies were published according to surgical SUI management evaluating and comparing therapy options and outcomes. Therapy options were evaluated using a Medline search, including only publications in English between 2000-2012. Key words used were: SUI, conservative and surgical treatment, midurethral sling, colposuspension. Surgical treatment options demonstrate significantly better results than conservative treatment. MUS demonstrate better subjective and objective cure rates than colposuspension; it is less invasive and more cost-effective. First line SUI therapy such as RP MUS and TVT seem to be favored when compared to transobturator techniques. Retropubic and transobturator MUS showed equivalent objective and subjective success rates. Open colposuspension is an effective treatment possibility for recurrent SUI after failed MUS. TVT, compared with other MUS, seems to show slightly better cure rates. but perioperative complications appear to be similar. Long-term results (>10 years) of repeated SUI surgery showed that the Burch procedure had the lowest 9-year cumulative incidence of repeat SUI surgery. Mini-sling techniques may be underestimated but long-time results are pending and closer monitoring of the adverse event profile must be carried out. MUS are first choice in the treatment of SUI, of which TVT, has the best cure rate. Colpussupension continues to have its place in recurrent SUI. The new mini-MUS needs a longer follow-up for final evaluation.

[Laparoendoscopic single-site surgery in urology using reusable systems]

PURPOSE

Many disposable platforms have been available for laparoendoscopic single-site surgery (LESS) for a long time. Besides technical challenges cost remains the limiting factor for the widespread use of LESS. We present our experiences with the first completely reusable LESS platform.

METHODS

We performed LESS procedures in 52 patients, including nephrectomy (n=18), adrenalectomy (2), partial nephrectomy (3), pyeloplasty (4), renal cyst ablation (4), pelvic lymphadenectomy (15) and lymphocele ablation (6). All procedures were carried out using a novel reusable single-port device (X-ConeR, Karl-Storz) with a simplified combination of standard and preformed instruments. Perioperative and demographic data including a visual analogue pain scale (VAS) were obtained. Complications were recorded using the Clavien classification.

RESULTS

The mean age of the patients was 50.04 years. Conversion to standard laparoscopy was necessary in 3 cases and the additional use of a 3 mm needle instrument in 6 cases. There were no open conversions. Intraoperative and postoperative complications occurred in 3 (Clavien II in 2 and III in 1) cases. Mean operating time was 110, 90, and 89 min and hospital stay was 4.9, 3.1 and 3.6 days for nephrectomy, pelvic lymphadenectomy, and pyeloplasty, respectively. The mean VAS was 2.13, 1.07 and 1.5 while blood loss was 81.3 ml, 25.67 ml and 17.5 ml, respectively.

CONCLUSIONS

The LESS technique with a completely reusable platform is applicable to various indications in urology yielding favorable functional and cosmetic results. This novel simplified combination of instruments facilitates handling and shortens the learning curve. Reusable materials may help to reduce cost leading to a wider acceptance of LESS.

[Minimally invasive percutaneous treatment of lower pole stones with a diameter of 8 to 15 millimeters]

PURPOSE

The optimal treatment options for lower pole stones with a diameter below 15 mm are controversially discussed. Extracorporeal shock wave lithotripsy (ESWL) is non-invasive but is hampered by low stone-free rates and a significant retreatment rate. Flexible ureterorenoscopy (URS) has been demonstrated to have high stone-free rates but the treatment costs - consisting of OR time, repair costs and expenditure for laser fibers, guide wires and stone baskets - as well as low stone-free rates with increasing stone size render this procedure highly expensive. Minimally invasive percutaneous litholapaxy (MIP) has shown low morbidity and high efficacy in the treatment of nephrolithiasis. The goal of this study was to investigate the efficacy and -safety of MIP for the treatment of small lower pole stones.

PATIENTS AND METHOD

The charts of 29 patients who were treated with MIP were reviewed and clinical data like OR time, drop in haemoglobin, complication rate, stone-free rate and duration of hospital stay were collected.

RESULTS

28 of 29 patients were primarily stone-free; one had to undergo additional flexible URS to become stone-free. All procedures were undertaken with only one access, no severe complications occurred; none of the patients had to be transfused.

CONCLUSIONS

The MIP concept has a low complication rate and has been shown to be safe and effective in previous studies. We demonstrate that the feasibility and efficacy justify the percutaneous approach also for small lower pole stones.

The effect of the erg26-1 mutation on the regulation of lipid metabolism in Saccharomyces cerevisiae

A temperature-sensitive Saccharomyces cerevisiae mutant harboring a lesion in the ERG26 gene has been isolated. ERG26 encodes 4alpha-carboxysterol-C3 dehydrogenase, one of three enzymatic activities required for the conversion of 4,4-dimethylzymosterol to zymosterol. Gas chromatography/mass spectrometry analyses of sterols in this mutant, designated erg26-1, revealed the aberrant accumulation of a 4-methyl-4-carboxy zymosterol intermediate, as well as a novel 4-carboxysterol. Neutral lipid radiolabeling studies showed that erg26-1 cells also harbored defects in the rate of biosynthesis and steady-state levels of mono-, di-, and triglycerides. Phospholipid radiolabeling studies showed defects in the rate of biosynthesis of both phosphatidic acid and phosphatidylinositol. Biochemical studies revealed that microsomes isolated from erg26-1 cells contained greatly reduced 4alpha-carboxysterol-C3 dehydrogenase activity when compared with microsomes from wild type cells. Previous studies have shown that loss of function mutations in either of the fatty acid elongase genes SUR4/ELO3 or FEN1/GNS1/ELO2 can "bypass" the essentiality of certain ERG genes (Ladeveze, V., Marcireau, C., Delourme, D., and Karst, F. (1993) Lipids 28, 907-912; Silve, S., Leplatois, P., Josse, A., Dupuy, P. H., Lanau, C., Kaghad, M., Dhers, C., Picard, C., Rahier, A., Taton, M., Le Fur, G., Caput, D., Ferrara, P., and Loison, G. (1996) Mol. Cell. Biol. 16, 2719-2727). Studies presented here have shown that this sphingolipid-dependent "bypass" mechanism did not suppress the essential requirement for zymosterol biosynthesis. However, studies aimed at understanding the underlying physiology behind the temperature-sensitive growth defect of erg26-1 cells showed that the addition of several antifungal compounds to the growth media of erg26-1 cells could suppress the temperature-sensitive growth defect. Fluorescence microscopic analysis showed that GFP-Erg26p and GFP-Erg27p fusion proteins were localized to the endoplasmic reticulum. Two-hybrid analysis indicated that Erg25p, Erg26p, and Erg27p, which are required for the biosynthesis of zymosterol, form a complex within the cell.

The cloning and overexpression of a cruciform binding protein from Ustilago maydis

The structural gene HMP1 encoding a cruciform DNA binding protein from Ustilago maydis has been cloned. Gene isolation was enabled by a polymerase chain reaction procedure using primers designed from amino acid sequence obtained from the purified protein. DNA sequence determination has revealed that the gene encodes a protein containing 98 amino acids with a calculated molecular weight of 10151. Comparison of the cDNA and genomic sequences indicated the presence of a single intron in the 5' coding region of the gene. The gene was over-expressed as a translational fusion with a hexahistidine leader sequence enabling affinity purification of the protein on an immobilized metal matrix. Protein isolated after over-expression exhibited cruciform binding activity, conforming earlier purified native protein results. Sequence analysis indicated that no HMG box was present and very little homology to other known cruciform binding proteins was found. It is plausible that HMP1 represents a novel class of proteins that recognize such secondary structures.

Immuno-electron-microscopic studies on the subcellular distribution of rat liver epoxide hydrolase and the effect of phenobarbitone and 2-acetamidofluorene treatment

The distribution of rat liver epoxide hydrolase in various subcellular fractions was investigated by immuno-electron-microscopy. Ferritin-linked monospecific anti-(epoxide hydrolase) immunoglobulins bound specifically to the cytoplasmic surfaces of total microsomal preparations and smooth and rough microsomal fractions as well as the nuclear envelope. Specific binding was not observed when the ferritin conjugates were incubated with peroxisomes, lysosomes and mitochondria. The average specific ferritin load of the individual subcellular fractions correlated well with the measured epoxide hydrolase activities. This correlation was observed with fractions prepared from control, phenobarbitone-treated and 2-acetamidofluorene-treated rats.

[Cooperation of the general practitioner with the specialist and the university institute]

When considering the areas in which a periodontist is needed, the degree of collaboration with the general practitioner appears. The various types as well as the level of cooperation are discussed. Moreover, the possibilities and limits of treatment of periodontal disease in the corresponding departments of Swiss Universities are mentioned. Cooperations between practitioner and periodontist or University departments should develop further, provided that the rules of professional ethics are observed.