Brain white matter expansion in human obesity and the recovering effect of dieting

CONTEXT AND OBJECTIVE: Obesity is associated with several metabolic abnormalities. Recent studies suggest that obesity also affects brain function and is a risk factor for some degenerative brain diseases. The objective of this study was to examine the effects of weight gain and weight loss on brain gray and white matter structure. We hypothesized that possible differences seen in the brains of obese subjects would disappear or diminish after an intensive dieting period. METHODS: In part I of the study, we scanned with magnetic resonance imaging 16 lean (mean body mass index, 22 kg/m(2)) and 30 obese (mean body mass index, 33 kg/m(2)) healthy subjects. In part II, 16 obese subjects continued with a very low-calorie diet for 6 wk, after which they were scanned again. Regional brain white and gray matter volumes were calculated using voxel-based morphometry. RESULTS: White matter volumes were greater in obese subjects, compared with lean subjects in several basal brain regions, and obese individuals showed a positive correlation between white matter volume in basal brain structures and waist to hip ratio. The detected white matter expansion was partially reversed by dieting. Regional gray matter volumes did not differ significantly in obese and lean subjects, and dieting did not affect gray matter. CONCLUSIONS: The precise mechanism for the discovered white matter changes remains unclear, but the present study demonstrates that obesity and dieting are associated with opposite changes in brain structure. It is not excluded that white matter expansion in obesity has a role in the neuropathogenesis of degenerative brain diseases.     

Diazepam binding inhibitor overexpression in mice causes hydrocephalus, decreases plasticity in excitatory synapses and impairs hippocampus-dependent learning

Diazepam binding inhibitor (DBI) and its processing products are endogenous modulators of GABAA and linked to various brain disorders ranging from anxiety and drug dependence to epilepsy. To investigate the physiological role of endogenously expressed DBI in the brain we created a transgenic mouse line overexpressing DBI gene. Transgenic mice had a 37x increased protein expression and immunohistochemistry showed excessive glial expression in the infragranular region of the dentate gyrus. Transgenic animals had significantly larger lateral ventricles and decreased plasticity of excitatory synapses without affecting either inhibitory or excitatory synaptic transmission. In behavioral tests transgenic animals had no differences in motor and exploratory activity, yet impaired hippocampus-dependent learning and memory. Overexpression did not cause anxiety or proconflict behavior, nor influenced kainic acid or pentylenetetrazole induced seizure activity. Our transgenic mouse line demonstrates that endogenously overexpressed DBI impairs hippocampus-dependent learning without anxiety or proconflict behavior.     

Striatal FDOPA uptake and cognition in advanced non-demented Parkinson's disease: a clinical and FDOPA-PET study

This study sought to determine the nature of the relationship between cognition and striatal dopaminergic functioning in 28 patients with advanced Parkinson's disease (PD) using fluorodopa Positron emission tomography (FDOPA-PET) and neuropsychological test scores. Mental flexibility was related to putamen activity while mental organization (executive memory and fluency) was related to caudate FDOPA uptake. Interestingly, the caudate may be more important in the mental components of executive functioning, while the putamen may be more important in the motor components of executive functioning.     

Dopamine Receptors in Parkinson's Disease: A Meta-Analysis of Imaging Studies

Dopamine receptors are abundant along the central nigrostriatal tract and are expressed as 5 subtypes in two receptor families. In PD, compensatory changes in dopamine receptors emerge as a consequence of the loss of dopamine nerve terminals or dopaminergic pharmacotherapy. We performed a systematic review and meta-analysis of the available PET and single-photon emission computed tomography studies that have investigated dopamine receptors in PD, PSP and MSA. The inclusion criteria were studies including human PET or single-photon emission computed tomography imaging; dopamine receptor tracers (D1-like or D2-like) and idiopathic PD, PSP, or MSA patients compared with healthy controls. The 67 included D2-like studies had 1925 patients. Data were insufficient for an analysis of D1-like studies. PD patients had higher striatal binding early in the disease, but after a disease duration of 4.36 years, PD patients had lower binding values than healthy controls. Striatal D2R binding was highest in unmedicated early PD patients and in the striatum contralateral to the predominant motor symptoms. PSP and MSA-P patients had lower striatal D2R binding than PD patients (14.2% and 21.8%, respectively). There is initial upregulation of striatal D2Rs in PD, which downregulate on average 4 years after motor symptom onset, possibly because of agonist-induced effects. The consistent upregulation of D2Rs in the PD striatum contralateral to the predominant motor symptoms indicates that receptor changes are driven by neurodegeneration and loss of striatal neuropil. Both PSP and MSA patients have clearly lower striatal D2R binding values than PD patients, which offers an opportunity for differential diagnostics. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society     

EAU guidelines on non-muscle-invasive urothelial carcinoma of the bladder

CONTEXT AND OBJECTIVE: To present the updated version of 2008 European Association of Urology (EAU) guidelines on non-muscle-invasive bladder cancer. EVIDENCE ACQUISITION: A systematic review of the recent literature on the diagnosis and treatment of non-muscle-invasive bladder cancer was performed. The guidelines were updated and the level of evidence and grade of recommendation were assigned. EVIDENCE SYNTHESIS: The diagnosis of bladder cancer depends on cystoscopy and histologic evaluation of the resected tissue. A complete and correct transurethral resection (TUR) is essential for the prognosis of the patient. When the initial resection is incomplete or when a high-grade or T1 tumour is detected, a second TUR within 2-6 wk should be performed. The short- and long-term risks of both recurrence and progression may be estimated for individual patients using the scoring system and risk tables. The stratification of patients to low, intermediate, and high-risk groups-separately for recurrence and progression-represents the cornerstone for indication of adjuvant treatment. In patients at low risk of tumour recurrence and progression, one immediate instillation of chemotherapy is strongly recommended. In those at an intermediate or high risk of recurrence and an intermediate risk of progression, one immediate instillation of chemotherapy should be followed by further instillations of chemotherapy or a minimum of 1 yr of bacillus Calmette-Guerin (BCG). In patients at high risk of tumour progression, after an immediate instillation of chemotherapy, intravesical BCG for at least 1 yr is indicated. Immediate cystectomy may be offered to the highest risk patients and in patients with BCG failure. The long version of the guidelines is available on www.uroweb.org. CONCLUSIONS: These EAU guidelines present the updated information about the diagnosis and treatment of non-muscle-invasive bladder cancer and offer the recent findings for the routine clinical application.     

Candidate susceptibility variants for esophageal squamous cell carcinoma

Esophageal cancer is common worldwide, and often fatal. The major histological subtype is esophageal squamous cell carcinoma (ESCC). ESCC shows familial aggregation and high heritability. Mutations in RHBDF2 cause tylosis, a very rare disorder characterized by high life‐time risk of ESCC, but no other well‐established predisposition genes have been identified. To identify candidate susceptibility variants for ESCC we utilized the Population Information System and the Finnish cancer registry to find study materials by clustering ESCC patients by family name at birth and municipality at birth. We collected archival tissue material and exome sequenced a total of 30 ESCC cases. We prioritized shared, deleterious and rare variants that were significantly enriched in our sample set compared to Finnish and population subset specific controls. Six variants passed filtering, the most frequent being a nonsense mutation in DNAH9 (p.Tyr1573Ter) found in four unrelated patients. DNAH9 has been reported to be frequently lost in ESCC tumors. In this study, one patient's tumor showed loss of the wild type allele of DNAH9 suggesting a tumor suppressive function. A missense variant in GKAP1 was shared by three patients, and missense variants in BAG1, NFX1, FUK, and DDOST by two each. EP300 which has previously been implicated in the genesis of ESCC had a missense variant segregating in three affected individuals in a single family. If validated in independent patient sets, these variants could serve as a tool towards prevention and early diagnosis of ESCC.     

Group IIA phospholipase A2 content of tears in patients with keratoconjunctivitis sicca

PURPOSE: To determine the concentration of group IIA phospholipase A2 (GIIAPLA(2)) in tears of patients with keratoconjunctivitis sicca (KCS) and to compare it with the GIIAPLA(2) content of tears in age-matched healthy controls. METHODS: The GIIAPLA(2)content of tears was measured with time-resolved fluoroimmunoassay in 20 patients with KCS (mean age 70.7+/-8.7 years) and in 20 normal subjects (mean age 70.2+/-9.9 years). RESULTS: The GIIAPLA(2)content of tears in patients with KCS was 75.8+/-54.2 microg/ml and in normal subjects it was 34.2+/-21.4 microg/ml. The difference was statistically significant. In patients with KCS the GIIAPLA(2) concentration slightly increased with decreasing Schirmer test values (Spearman's correlation =-0.20) CONCLUSION: The results of this study indicate that in patients with KCS the relative concentration of GIIAPLA(2) of tears was increased due to decreased aqueous production in the lacrimal glands and better preservation of the acinar cells in the central parts of the lobules of the lacrimal glands producing GIIAPLA(2).