Modeling movement disorders--CRPS-related dystonia explained by abnormal proprioceptive reflexes

Humans control their movements using adaptive proprioceptive feedback from muscle afferents. The interaction between proprioceptive reflexes and biomechanical properties of the limb is essential in understanding the etiology of movement disorders. A non-linear neuromuscular model of the wrist incorporating muscle dynamics and neural control was developed to test hypotheses on fixed dystonia. Dystonia entails sustained muscle contractions resulting in abnormal postures. Lack of inhibition is often hypothesized to result in hyperreflexia (exaggerated reflexes), which may cause fixed dystonia. In this study the model-simulated behavior in case of several abnormal reflex settings was compared to the clinical features of dystonia: abnormal posture, sustained muscle contraction, increased stiffness, diminished voluntary control and activity-aggravation. The simulation results were rated to criteria based on characteristic features of dystonia. Three abnormal reflex scenarios were tested: (1) increased reflex sensitivity-increased sensitivity of both the agonistic and antagonistic reflex pathways; (2) imbalanced reflex offset-a static offset to the reflex pathways on the agonistic side only; and (3) imbalanced reflex sensitivity-increased sensitivity of only the agonistic reflex pathways. Increased reflex sensitivity did not fully account for the features of dystonia, despite distinct motor dysfunction, since no abnormal postures occurred. Although imbalanced reflex offset did result in an abnormal posture, it could not satisfy other criteria. Nevertheless, imbalanced reflex sensitivity with unstable force feedback in one of the antagonists closely resembled all features of dystonia. The developed neuromuscular model is an effective tool to test hypotheses on the underlying pathophysiology of movement disorders.     

Update on allergic fungal rhinosinusitis

The combination of nasal polyposis, crust formation, and sinus cultures yielding Aspergillus was first noted in 1976 by Safirstein, who observed the clinical similarity that this constellation of findings shared with allergic bronchopulmonary Aspergillosis. Eventually this disease came to be known as allergic fungal rhinosinusitis (AFRS). As clinical evidence on AFRS continues to accumulate, controversy regarding its etiology, pathogenesis, natural history, and appropriate treatment naturally has emerged. Despite past and current efforts, many of these controversies remain incompletely resolved, but continuing clinical study has illuminated some aspects of the disease and has led to an improved understanding of AFRS and its treatment. This article is intended to review current data and theories regarding the pathophysiology and clinical presentation of AFRS, as well as the role of various surgical and nonsurgical forms of therapy.     

The endogenous opioid system in neurological disorders of the basal ganglia

The endogenous opioid peptides have for some time been implicated in the regulation of motor behavior in animals. Recently, however, there is increased evidence to suggest a role for these peptides in the control of human motor functions as well as in the pathophysiology of abnormal movement disorders. Degeneration of opioid peptide-containing neurons in the basal ganglia has been demonstrated in Parkinson's disease and Huntington's chorea, but the clinical significance of these findings is largely unknown. On the other hand, there is evidence that excessive opioid activity may be important in the pathophysiology of some movement disorders such as tardive dyskinesia, progressive supra-nuclear palsy, and a subgroup of Tourette's patients. These findings indicate that diseases of the basal ganglia are possibly associated with alterations in opioid peptide activity, and that these alterations may be useful in designing experimental therapeutic strategies in these conditions.     

Association of inflammatory markers elevation with aggressive behavior in domestic dogs

We tested the hypothesis that elevations of inflammatory markers such as C-reactive protein (CRP) and interleukin-6 (IL-6) could be associated with the presence of aggressive behavior in domestic dogs. Serum concentrations of CRP and IL-6 were determined by ELISA in eighteen adult male German Shepherd dogs showing no clinical signs but aggression. Eighteen healthy male dogs with a negative history of behavioral and neurological disorders were used as controls. Compared with normal dogs, those with aggression had significantly higher levels of CRP (P < 0.05) and IL-6 (P < 0.01) after adjustment for age, body weight, creatinine, blood urea nitrogen, total protein, total bilirubin and cholesterol. Our pilot data suggest for the first time that an activation of systemic inflammatory processes may contribute to the pathophysiology of aggression in domestic dogs. Further investigations are needed regarding the impact of our findings on treatment strategies.     

Laboratory diagnosis of congenital disorders of glycosylation type I by analysis of transferrin glycoforms

Congenital disorders of glycosylation (CDG) are being recognized as a rapidly growing and complex group of disorders. The pathophysiology results from depressed synthesis or remodeling of oligosaccharide moieties of glycoproteins. The ultimate result is the formation of abnormal glycoproteins affecting their structure and metabolic functions. The most thoroughly studied subset of CDG are the type I defects affecting N-glycosylation. Causal mutations occur in at least 12 different genes which encode primarily monosaccharide transferases necessary for N-glycosylation in the endoplasmic reticulum. The broad clinical presentation of these glycosylation defects challenge clinicians to test for these defects in a variety of clinical settings. The first described CDG was a phosphomannomutase deficiency (CDG-Ia). The original method used to define the glycosylation defect was isoelectric focusing (IEF) of transferrin. More recently, the use of other charge separation methods and electrospray-mass spectrometry (ESI-MS) has proven valuable in detecting type I CDG defects. By mass resolution, the under-glycosylation of transferrin is characterized as the total absence of one or both N-linked oligosaccharide. Beyond providing a new understanding of the structure of transferrin in type I CDG patients, it is adaptable to high throughput serum analysis. The use of transferrin under-glycosylation to detect the type I CDG provides limited insight into the specific site of the defect in oligosaccharide assembly since its value is constrained to observation of the final product of glycoprotein synthesis. New analytical targets and tools are converging with the clinical need for diagnosis of CDG. Defining the biosynthetic sites responsible for specific CDG phenotypes is in progress, and ten more type I defects have been putatively identified. This review discusses current methods, such as IEF and targeted proteomics using mass spectrometry, that are used routinely to test for type I CDG disorders, along with some newer approaches to define the defective synthetic sites responsible for the type I CDG defects. All diagnostic endeavors are followed by the quest for a reliable treatment. The isolated success of CDG-Ib treatment will be described with the hope that this may expand to other type I CDG disorders.     

LMNA-linked lipodystrophies: from altered fat distribution to cellular alterations

Mutations in the LMNA gene, encoding the nuclear intermediate filaments the A-type lamins, result in a wide variety of diseases known as laminopathies. Some of them, such as familial partial lipodystrophy of Dunnigan and metabolic laminopathies, are characterized by lipodystrophic syndromes with altered fat distribution and severe metabolic alterations with insulin resistance and dyslipidaemia. Metabolic disturbances could be due either to the inability of adipose tissue to adequately store triacylglycerols or to other cellular alterations linked to A-type lamin mutations. Indeed, abnormal prelamin A accumulation and farnesylation, which are clearly involved in laminopathic premature aging syndromes, could play important roles in lipodystrophies. In addition, gene expression alterations, and signalling abnormalities affecting SREBP1 (sterol-regulatory-element-binding protein 1) and MAPK (mitogen-activated protein kinase) pathways, could participate in the pathophysiological mechanisms leading to LMNA (lamin A/C)-linked metabolic alterations and lipodystrophies. In the present review, we describe the clinical phenotype of LMNA-linked lipodystrophies and discuss the current physiological and biochemical hypotheses regarding the pathophysiology of these diseases.     

Regional fat deposition in the legs is useful as a presumptive marker of antiatherogenesity in Japanese

To examine the pathological role of regional fat deposition in development of metabolic and cardiovascular disorders, regional fat distribution was evaluated using metabolites and hormones as measures of obesity-related disorders. The subjects enrolled were 100 sex-matched inpatients, who were admitted, regardless of their body mass index values, for further examination of unusual results from periodic medical screening tests, and for examination of obesity-induced complications and treatment of obesity. Body fat distribution was analyzed using dual energy X-ray absorptiometry (DEXA). Analysis of parameters regarding fat distribution showed that gender was one of the determinants affecting correlation between fat distribution and metabolites of fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), total cholesterol (TC), or triglyceride (TG). However, regardless of gender, both leg trunk fat (L/Tr) and arm trunk fat (A/Tr) ratios negatively correlated with a total body fat (% total fat) ratio, whereas the intercept value of female regression line in L/Tr was greater than that in males, but not in A/Tr. Percentage total fat, L/Tr, and A/Tr in males correlated significantly with FPG, TC, TG, low-density lipoprotein (LDL), very low density lipoprotein (VLDL), atherogenic index (A.I.), and apoB/A1 only low density lipoprotein (LDL) was significantly correlated solely to L/Tr and A/Tr. These results indicate that regional fat distribution in males may not be a major determinant for development of metabolic disorders in obese patients. Unlike male regional fat distribution, female L/Tr correlated significantly not only with TC, TG, and LDL, but also with FPG and HbA1c, although both of the latter 2 glucose-related parameters in males showed no correlation with any parameters of fat deposition. The remaining female parameters of fasting plasma insulin, VLDL, A.I., and ApoB/A1 correlated with each of the three parameters of fat deposition, as similarly shown in males. The powerful and negative correlation was thus evident, particularly in females, between leg fat deposition and parameters of glucose and lipid metabolites. The resulting information provides a novel insight that regional fat deposition at the legs is useful as a marker for metabolic and cardiovascular disorders associated with obesity.     

Overexpression of TNF-α in mitochondrial diseases caused by mutations in mtDNA: evidence for signaling through its receptors on mitochondria

Mitochondrial diseases (MDs) are heterogeneous disorders due to impaired respiratory chain function causing defective ATP production. Although the disruption of oxidative phosphorylation is central to the MD pathophysiology, other factors may contribute to these disorders. We investigated the expression and the cellular localization of TNF-α and its receptors, TNFR1 and TNFR2, in muscle biopsies from 15 patients with mitochondrial respiratory chain dysfunction. Our data unambiguously demonstrate that TNF-α is expressed in muscle fibers with abnormal focal accumulations of mitochondria, so-called ragged red fibers, and is delivered to mitochondria where both receptors are localized. Moreover TNF receptors are differentially regulated in patients' muscle in which the expression levels of TNFR1 mRNA are decreased and those of TNFR2 mRNA are increased compared with controls. These findings suggest for the first time that TNF-α could exert a direct effect on mitochondria via its receptors.     

Reconsideration of bipolar disorder as a developmental disorder: Importance of the time of onset

Bipolar disorder is a multifactorial psychiatric disorder with developmental and progressive neurophysiological alterations. This disorder is typically characterized by cyclical and recurrent episodes of mania and depression but is heterogeneous in its clinical presentation and outcome. Although the DSM-IV-TR criteria identify several features that are of phenomenological relevance, these are of less utility for defining homogeneous subgroups, for analyses of correlations with biomarkers or for directing focused medication strategies. We provide a comprehensive review of existing evidence regarding to age at onset in bipolar disorder. Eight admixture studies demonstrate three homogeneous subgroups of patients with bipolar disorder identified according to age at onset (early, intermediate and late age at onset), with two cutoff points, at 21 and 34 years. It is suggested that the early-onset subgroup has specific clinical features and outcomes different from those of the other subgroups. Early-onset subgroup may be considered a more suitable clinical phenotype for the identification of susceptibility genes with recent data demonstrating associations with genetic variants specifically in this subgroup. The use of age at onset as a specifier may also facilitate the identification of other biological markers for use in brain imaging, circadian, inflammatory and cognitive research. A key challenge is posed by the use of age at onset in treatment decision algorithms, although further research is required to increase the evidence-base. We discuss three potential benefits of specifying age at onset, namely: focused medication strategies, the targeted prevention of specific comorbid conditions and decreasing the duration of untreated illness. We argue that age at onset should be included as a specifier for bipolar disorders.     

Effect of Degree of Weight Loss on Health Benefits

Although most dieters strive to achieve “ideal” body weight, clinical and laboratory evidence clearly supports the value of a modest weight loss goalto attain health and emotional benefit. Weight loss as low as 5% has been shown to reduce or eliminate disorders associated with obesity, though several questions remain partially or completely unanswered regarding the roles of degree of weight loss, method of weight loss, distribution of fat reduction, and other variables. This paper reviews the effect of degree of weight loss on specific disease states and risk factors and discusses the impact of ethnic background at distribution, age, and mode of weight loss on outcome.     

The role of α-synuclein in the pathophysiology of alcoholism

Alcoholism has complex etiology and there is evidence for both genetic and environmental factors in its pathophysiology. Chronic, long-term alcohol abuse and alcohol dependence are associated with neuronal loss with the prefrontal cortex being particularly susceptible to neurotoxic damage. This brain region is involved in the development and persistence of alcohol addiction and neurotoxic damage is likely to exacerbate the reinforcing effects of alcohol and may hinder treatment. Understanding the mechanism of alcohol’s neurotoxic effects on the brain and the genetic risk factors associated with alcohol abuse are the focus of current research. Because of its well-established role in neurodegenerative and neuropsychological disorders, and its emerging role in the pathophysiology of addiction, here we review the genetic and epigenetic factors involved in regulating α-synuclein expression and its potential role in the pathophysiology of chronic alcohol abuse. Elucidation of the mechanisms of α-synuclein regulation may prove beneficial in understanding the role of this key synaptic protein in disease and its potential for therapeutic modulation in the treatment of substance use disorders as well as other neurodegenerative diseases.     

Unplanned cancer presentation in patients with psychiatric disorders: A nationwide register-based cohort study in Denmark

Unplanned presentation in the cancer pathway is more common in patients with psychiatric disorders than in patients without. More knowledge about the risk factors for unplanned presentation could help target interventions to ensure earlier diagnosis of cancer in patients with psychiatric disorders. This study aims to estimate the association between patient characteristics (social characteristics and coexisting physical morbidity) and cancer diagnosis following unplanned presentation among cancer patients with psychiatric disorders. We conducted a population-based register study including patients diagnosed with cancer in 2014–2018 and also registered with at least one psychiatric disorder in the included Danish registers (n = 26,005). We used logistic regression to assess patient characteristics associated with an unplanned presentation. Almost one in four symptomatic patients (23.6 %) with pre-existing psychiatric disorders presented unplanned in the cancer trajectory. Unplanned presentation was most common for severe psychiatric disorders, e.g. organic disorders and schizophrenia. Old age, male sex, living alone, low education, physical comorbidity, and non-attendance in primary care were associated with increased odds of unplanned presentation. In conclusion, several characteristics of patients with pre-existing psychiatric disorders were associated with unplanned presentation in the cancer trajectory; for some groups more than 40 % had an unplanned presentation. This information could be used to design targeted interventions for patients with pre-existing psychiatric disorders to ensure earlier diagnosis of cancer in this population.     

The role of inflammation,oxidative stress,angiogenesis, and apoptosis in the pathophysiology of endometriosis: Basic science and new insights based on gene expression

Endometriosis is a frequent and chronic illness in young women which could be defined by the existence of endometrial stroma and glands outside of the normal site of the lining of the uterus. It has painful symptoms. The advanced stage of endometriosis may lead to gynecological malignancies, such as ovarian cancer, and other complications, including infertility. However, its exact physiopathology is not well known. Recent studies have shown the possible roles of inflammation along with oxidative stress. Additionally, angiogenesis and apoptosis dysregulation contribute to endometriosis pathophysiology. Therapeutic strategies and continuing attempts, to conquer endometriosis should be done regarding molecular signaling pathways. Thus, the present review summarizes current studies and focuses on molecular mechanisms.     

Role of cervical dendritic cell subsets,co-stimulatory molecules,cytokine secretion profile and beta-estradiol in development of sequalae to Chlamydia trachomatis infection

Background  

Chlamydia trachomatis infection of the female genital tract can lead to serious sequelae resulting in fertility related disorders. Little is known about the mechanism leading to Chlamydia induced pathology and factors responsible for it. As only some of the women develops reproductive disorders while majority of the women clears infection without any severe sequalae, mucosal immune response in women with or without fertility disorders was studied to identify factors which may lead to final clinical outcome of chlamydial infection.     

Muscarinic activation attenuates abnormal processing of β-amyloid precursor protein induced by cobalt chloride-mimetic hypoxia in retinal ganglion cells

β-Amyloid peptide (Aβ), the major pathological factor in Alzheimer’s disease, has recently been reported to be implicated in the development of glaucoma. In this study, we explored the effect of muscarinic activation on abnormal processing of β-amyloid precursor protein (APP) induced by a risk factor hypoxia in retinal ganglion cells. Hypoxia mimetic compound cobalt chloride could increase the generation of Aβ via up-regulating the expression of APP as well as the expression of β-secretase and γ-secretase, whereas muscarinic receptor agonist pilocarpine could significantly attenuate this abnormal pathway, thereby resulting in a decreased amyloidogenic cleavage of APP. This finding may provide an insight into better understanding of pathophysiology for the retinal neurodegenerative disease and searching for its new modifying approach.     

Monocyte subpopulations from pre-eclamptic patients are abnormally skewed and exhibit exaggerated responses to toll-like receptor ligands

The leading cause of pregnancy-associated mortality and morbidity is pre-eclampsia (PE). Although information regarding the etiology of this disease is scant, its pathophysiology is characterized by abnormal placentation, endothelial dysfunction as well as an exaggerated inflammatory response. Clinical evidence also indicates that the abundance of many immune cells at the feto-maternal interface and in the circulation of PE patients is abnormal, when compared with normal pregnant (NP) controls. In addition, the phenotype and function of some of these cells is altered. To further characterize the systemic effects of PE on circulating cells, we analyzed monocytic subpopulations in NP and PE patients by flow cytometry. We found that non-classical CD14(low)CD16(+) monocytes are significantly increased in women with PE and they display irregular expression of several chemokine receptors and antigen presentation molecules. The most striking phenotypic difference among the cell surface molecules was the marked upregulation of TLR4 expression, where both CD14(high)CD16(+) and CD14(low)CD16(+) monocytes demonstrated higher levels than their NP counterparts. Stimulation of PE monocytes with TLR ligands resulted in profound secretion of various cytokines in comparison with NP controls. These data suggest that PE monocytes are hyper-responsive to TLR ligands and this may contribute to exacerbation of the disease.     

Atypical Clinical Presentation of Acth-Dependent Cushing's Syndrome in a Patient Treated with Retinoic Acid

ObjectiveThe leading signs and symptoms of Cushing’s syndrome (CS) in adolescents, which depend on the duration and the severity of hypercortisolemia, are: a decrease in growth velocity with an increase in body weight, redistribution of fat tissue (round face), and less commonly, acne due to hyperandrogenization. A widely used antiacne drug, retinoic acid, can change the clinical presentation of CS and delay the diagnosis.MethodsWe report an atypical presentation of adrenocorticotropic hormone (ACTH)-dependent CS in a patient treated with retinoic acid due to severe acne.ResultsThree months after the discontinuation of retinoic acid treatment (at a dose of 40 mg daily for 6 months, with a 4 month break and then for an additional 6 months), a 17.5-year-old male presented with short stature (− 3.0 SD), muscle weakness, difficulty concentrating, insomnia, and depressed mood. Body weight (body mass index, 22 kg/m²), fat tissue distribution, pubertal status (testicular volume equal to 20 mL, pubarche V, axillarche present), and blood pressure were normal, and the patient’s bone age was equal to his chronologic age. His bone mineral density was decreased (Z-score, − 3.5 SD). The morning serum cortisol level was normal (8:00 am, 171.9 ng/mL) and did not decrease in the evening (8:00 pm, 178.9 ng/mL) or after 1 mg of dexamethasone (100.4 ng/mL). The patient’s urinary free cortisol was elevated on 3 occasions (274.5, 217.3, and 253.7 μg/day). Increased ACTH levels in the morning (97.5 to 141.1 pg/mL) and postcorticoliberine (577.6 pg/mL) pointed to ACTH-dependent CS. A magnetic resonance imaging scan of the pituitary gland confirmed the presence of a microadenoma.ConclusionRetinoic acid treatment may alter the clinical presentation of ACTH-dependent CS and consequently delay the diagnosis. (Endocr Pract. 2014;20:e119-e122)     

A mathematical model of twin-twin transfusion syndrome with pulsatile arterial circulations

The twin-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies caused by a net transfusion of blood from one twin (the donor) to the other (the recipient) through placental anastomoses. To examine the pathophysiology of TTTS evolving through clinical stages I to IV, we extended our mathematical model to include pulsating circulations propagating along the arterial tree as well as placental and cerebral vascular resistances, and arterial wall thickness and stiffness. The model demonstrates that abnormal umbilical arterial flow (TTTS stage III) in the donor twin results from increased placental resistance as well as reduced resistance in the cerebral arteries. In contrast, recipient twin abnormal umbilical arterial flow requires a significantly greater increase in placental resistance, resulting from the compressive effects of high amniotic fluid pressure. Thus simulated abnormalities of donor umbilical arterial pulsations occur in the donor more commonly and earlier than in the recipient. The "normal" staging sequence (I, II, III, IV) correlates with the presence of compensating placental anastomoses, constituting the majority of monochorionic twin placentas. However, TTTS stage III may occur before manifestations of stage II (lack of donor bladder filling), in our model correlating with severe TTTS from a single arteriovenous anastomosis, an infrequent occurring placental angioarchitecture. In conclusion, this mathematical model describes the onset and development of the four stages of TTTS, reproduces a variety of clinical manifestations, and may contribute to identifying the underlying pathophysiology of the staging sequence in TTTS.