Integrative metabolomics-genomics analysis identifies key networks in a stem cell-based model of schizophrenia

Schizophrenia (SCZ) is a neuropsychiatric disorder, caused by a combination of genetic and environmental factors. The etiology behind the disorder remains elusive although it is hypothesized to be associated with the aberrant response to neurotransmitters, such as dopamine and glutamate. Therefore, investigating the link between dysregulated metabolites and distorted neurodevelopment holds promise to offer valuable insights into the underlying mechanism of this complex disorder. In this study, we aimed to explore a presumed correlation between the transcriptome and the metabolome in a SCZ model based on patient-derived induced pluripotent stem cells (iPSCs). For this, iPSCs were differentiated towards cortical neurons and samples were collected longitudinally at various developmental stages, reflecting neuroepithelial-like cells, radial glia, young and mature neurons. The samples were analyzed by both RNA-sequencing and targeted metabolomics and the two modalities were used to construct integrative networks in silico. This multi-omics analysis revealed significant perturbations in the polyamine and gamma-aminobutyric acid (GABA) biosynthetic pathways during rosette maturation in SCZ lines. We particularly observed the downregulation of the glutamate decarboxylase encoding genes GAD1 and GAD2, as well as their protein product GAD65/67 and their biochemical product GABA in SCZ samples. Inhibition of ornithine decarboxylase resulted in further decrease of GABA levels suggesting a compensatory activation of the ornithine/putrescine pathway as an alternative route for GABA production. These findings indicate an imbalance of cortical excitatory/inhibitory dynamics occurring during early neurodevelopmental stages in SCZ. Our study supports the hypothesis of disruption of inhibitory circuits to be causative for SCZ and establishes a novel in silico approach that enables for integrative correlation of metabolic and transcriptomic data of psychiatric disease models.

Curative treatment of pelvic arteriovenous malformation--an alternative strategy: transvenous intra-operative embolisation

OBJECTIVES

Pelvic arteriovenous malformations (AVMs) are difficult to treat. Arterial embolisation is the most common strategy but often has poor results. We report an alternative surgical approach of controlled intra-operative transvenous embolisation with long-term results in seven cases.

MATERIALS AND METHODS

Between 1980 and 2008, we treated seven patients (four men, three women, mean age 50 years). Indications were rectal bleeding (one case), urinary tract problems (four cases), oedema of lower limb (one case) and high-output cardiac failure (one case). Four of them had previous operations and three had previous attempts for embolisation. Embolisation of the malformation was performed through the internal iliac vein. This was done after clamping of all the feeding and draining vessels. The agent used was cyanocrylate (one case), Ethibloc (one case) and bone wax (five cases).

RESULTS

Mortality was 0%. Complications occurred in two patients (28,5%), one pulmonary embolism and one regressive femoral paresis. Three patients were re-operated for various reasons. The mean follow-up period was 6 years (1-12 years). Symptoms resolved in all patients, while control by computed tomography (CT) angioscan revealed one residual shunt.

CONCLUSION

Complete surgical excision of pelvic AVMs is not always possible. Embolisation does not offer a permanent cure. Intra-operative transvenous embolisation of persisting complex AVMs appears to be an alternative approach with good immediate and long-term results. Ethylene glycol appears to be the most suitable agent.

Pancreatic mucinous cystadenoma communicating with the main pancreatic duct on MRI

We report a case of a mucinous cystadenoma of the pancreas communicating with the main pancreatic duct. To our knowledge, this is the first case in which a communication between the mucinous cystadenoma and the main pancreatic duct could be demonstrated by MRI.

Radiofrequency ablation of 100 hepatic metastases with a mean follow-up of more than 1 year

OBJECTIVE

The objective of our study was to evaluate the efficacy and safety of radiofrequency ablation of hepatic metastases performed either percutaneously for treatment of hepatic metastases in patients deemed ineligible for surgery or intraoperatively during partial hepatectomy to destroy unresectable metastases.

SUBJECTS AND METHODS

Sixty-eight patients with 121 hepatic metastases (<5 metastases per patient) that were mainly colorectal in origin underwent 76 sessions of radiofrequency ablation with cooled-needle electrodes under sonographic guidance. Twenty-one patients with 33 metastases of 5-20 mm in diameter (mean +/- SD,13 +/- 7 mm) underwent intraoperative radiofrequency ablation. Forty-seven patients with 88 metastases of 10 to 42 mm in diameter (mean +/- SD, 26 +/- 9 mm) were treated with percutaneous radiofrequency ablation. Procedure efficacy was evaluated with dynamic enhanced CT and MR imaging performed 2, 4, and 6 months after treatment and then every 3 months.

RESULTS

Radiofrequency ablation allowed eradication of 91% of the 100 treated metastases that were followed up for 4-23 months (mean, 13.7 months). Tumor control was equivalent for percutaneous radiofrequency ablation (90%) and for intraoperative radiofrequency ablation (94%). Failure to achieve tumor control occurred mostly with the largest tumor nodules. One bilioperitoneum and two abscesses were the major complications encountered after treatment of 121 metastases with a follow-up of more than 2 months.

CONCLUSION

Radiofrequency ablation appears to be a promising therapeutic modality capable of extending the possibilities of partial hepatectomy and of efficiently treating small metastases percutaneously.

Vasopressin V1a receptor signaling in a rat choroid plexus cell line

A new cell line was derived from primary culture of rat choroid plexus (RCP) by immortalization with the TSOri minus adenovirus. The selected clone expressed vasopressin V1a receptors at a density of 64,000 sites per cell, and a K(d) of 7.2 nM. Addition of vasopressin to the RCP cells induced a transient calcium peak comparable to V1a receptor signalling in different expression systems. This [Ca(2+)](i) increase was dose-dependent with an EC(50) of 22 nM vasopressin. Similar [Ca(2+)](i) increase was elicited by addition of serotonin, angiotensin II, endothelin-1, and bradykinin. Heterologous desensitization of V1a receptor was observed in RCP cells exposed to the phorbol ester PMA or following stimulation of other receptors coupled to the phosphoinositide pathway. Positive immunolabelling with Factor VIII, Flt1 and CD 34 antibodies suggests that this new RCP cell line originated from endothelial cells of rat choroid plexus.

Laser lithotripsy of difficult biliary stones

From June 1991 to September 1992, 16 patients (mean age, 72 +/- 5 years) were treated with intra-corporeal laser lithotripsy (ICL). Thirteen patients had choledocholithiasis with at least one stone larger than 20 mm; 3 patients had intra-hepatic lithiasis. All other methods, including mechanical lithotripsy, extra-corporeal lithotripsy (1 case), and intra-corporeal electrohydraulic lithotripsy (1 case), had failed to clear the bile ducts. Approaches for ICL were choledochoscopy with a "baby" endoscope via an existing sphincterotomy (8 cases), retrograde cholangioscopy with a gastroscope through a choledochoduodenal anastomosis or a sphincterotomy in patients with a gastrojejunal anastomosis (5 cases), and trans-hepatic cholangioscopy with a fibercholangioscope (3 cases, in 1 of which retrograde and trans-hepatic approaches were combined). Free bile ducts were obtained in 14/16 (87.5%) patients after a mean of 1.66 ICL sessions per patient. Mortality and laser-related morbidity did not occur; endoscopy-related morbidity was 12.5% for minor complications (1 transitory fever, 1 mild and transitory hemobilia) and 6.25% for major complications (1 post-sphincterotomy hemorrhage). Mean length of hospital stay was 11.5 +/- 2.5 days. We conclude that although it is rarely indicated and is expensive, ICL does offer a limited treatment option in selected patients. It allows the complete relief of complex biliary lithiasis. Morbidity is related to maneuvers preceding ICL, not to ICL itself.

[Palliative treatment by endoprosthesis of icterus caused by distal biliary tumoral obstruction]

Between March 1982 and December 1987, 466 patients (256 women, 210 men, mean age 73 years) with tumor obstruction of the common bile duct were referred to our department. The causes of obstruction were carcinoma of the pancreas (298 patients), carcinoma of the ampulla of Vater (32 patients) and carcinoma of the common bile duct (136 patients). Endoscopical insertion of a biliary prosthesis was initially possible in 377 patients (81%). In case of failure, patients were referred to the radiologist for percutaneous drainage. Successful drainage was obtained in 58 patients with an overall success rate of 93% (435 patients). Endoscopic replacement was necessary in 170 cases for 114 patients and was successful in 155 (91%). Pruritus was relieved in 89% of the patients. Serum bilirubin levels decreased more than 75% after initial endoscopic endoprosthesis, repeated endoscopic endoprosthesis and percutaneous prosthesis insertion in 80%, 79%, and 62% of the patients, respectively. Short term complications of endoscopic endoprosthesis occurred in 28% of patients with a mortality rate of 8%. Percutaneous prosthesis complications occurred in 33% of patients with a mortality rate of 11%. In the long term, cholangitis was the main complication and occurred in 27% of patients with a delay of 103 +/- 105 days. Intestinal obstruction was observed in 7% of patients. The average life expectancy of endoscopic endoprosthesis and percutaneous prosthesis was 109 +/- 157 and 92 +/- 101 days, respectively. The average life expectancy of patients was 163 +/- 224 days.(ABSTRACT TRUNCATED AT 250 WORDS)

[Isolated dissecting aneurysm of the superior mesenteric artery. Dysplasia, a rare cause of mesenteric ischemia. Report of a case]

We report a case of successful surgical revascularization of the superior mesenteric artery in a patient presenting with intestinal ischaemia due to fibrodysplasia. This is a rare pathology, with 5 cases operated in our institution and only 16 cases reported in the literature. Angiography may show other sites of arterial dysplasia. In such cases, success depends on early surgical revascularization.

[Takayasu's disease. Exploration by intra-arterial digital angiography. 50 cases]

The long-term prognosis of Takayasu's disease depends on an elective surgical treatment which requires full and accurate assessment of the lesions. We present here a retrospective study of 50 patients explored before surgery by intra-arterial digital angiography. In 92 percent of the patients the thoraco-abdominal aorta and its branches were well documented on 2 orthogonal projections performed in one single session. The high-quality intra-arterial opacification made it possible to detect incipient parietal lesions and to evaluate the lesions of the small caliber branches and the downstream bed in case of occlusion. These advantages, and the absence of morbidity in our experience, make digital panarteriography a method of choice to evaluate Takayasu's disease.