Craniofacial bone tissue engineering

There are numerous conditions, such as trauma, cancer, congenital malformations, and progressive deforming skeletal diseases, that can compromise the function and architectonics of bones of craniofacial region. The need to develop new approaches for treatment of these disorders arises from the fact that conventional therapeutic strategies face many obstacles and limitations. The use of tissue engineering in regeneration of craniofacial bone structures is a very promising possibility and a great challenge for researchers and practitioners. Developments in stem cell biology and engineering have led to the discovery of different stem cell populations and biodegradable materials with suitable properties. This review summarizes the current achievements in tissue engineering of craniofacial bone, temporomandibular joint, and periodontal ligament.     

The exposome in atopic dermatitis

Atopic dermatitis (AD) is a complex inflammatory disorder with multiple interactions between genetic, immune and external factors. The sum of external factors that an individual is exposed to throughout their lifetime is termed the exposome. The exposome spans multiple domains from population to molecular levels and, in combination with genetic factors, holds the key to understanding the phenotypic diversity seen in AD patients. Exposomal domains are categorized into nonspecific (human and natural factors affecting populations), specific (eg humidity, ultraviolet radiation, diet, pollution, allergens, water hardness) and internal (cutaneous and gut microbiota and host cell interaction) exposures. The skin, as the organ that most directly interacts with and adapts to the external environment, is a prime target for exploration of exposomal influences on disease. Given the well-recognized physical environmental influences on AD, this condition could be much better understood through insightful exposomal research. In this narrative review, we examine each domain in turn, highlighting current understanding of the mechanisms by which exposomal influences modulate AD pathogenesis at distinct points in time. We highlight current approaches to exposome modification in AD and other allergic disease and propose future directions for exposome characterization and modification using novel research techniques.     

Frequency selective neuronal modulation triggers spreading depolarizations in the rat endothelin-1 model of stroke

Ischemia is one of the most common causes of acquired brain injury. Central to its noxious sequelae are spreading depolarizations (SDs), waves of persistent depolarizations which start at the location of the flow obstruction and expand outwards leading to excitotoxic damage. The majority of acute stage of stroke studies to date have focused on the phenomenology of SDs and their association with brain damage. In the current work, we investigated the role of peri-injection zone pyramidal neurons in triggering SDs by optogenetic stimulation in an endothelin-1 rat model of focal ischemia. Our concurrent two photon fluorescence microscopy data and local field potential recordings indicated that a ≥ 60% drop in cortical arteriolar red blood cell velocity was associated with SDs at the ET-1 injection site. SDs were also observed in the peri-injection zone, which subsequently exhibited elevated neuronal activity in the low-frequency bands. Critically, SDs were triggered by low- but not high-frequency optogenetic stimulation of peri-injection zone pyramidal neurons. Our findings depict a complex etiology of SDs post focal ischemia and reveal that effects of neuronal modulation exhibit spectral and spatial selectivity.     

Vaginal leukocyte characteristics in urogenital trichomoniasis.

Morphological and functional characteristics of vaginal exudate leukocytes were examined in 47 patients with urogenital trichomoniasis. Electron microscopic morphology, viability, phagocytosis of Candida albicans blastospores and ability to undergo respiratory burst in the iodonitrotetrazolium reductase test were evaluated in these cells. Vaginal inflammatory leukocytes were almost exclusively polymorphonuclear neutrophils, and their concentration was positively correlated (r = 0.58; p less than 0.001) with the number of trichomonads in the exudate. Median leukocyte viability reached 39% and both phagocytic and tetrazolium reductase activities of these cells were significantly reduced in comparison with those of circulating polymorphonuclear leukocytes. Patients with a clinical picture of severe mucosal inflammation had significantly higher vaginal exudate leukocyte concentrations and viability than those without inflammatory signs. The possible role of vaginal leukocytes in the pathogenesis of urogenital trichomoniasis is discussed.     

Overlap Technique Improves Results of Primary Surgery after Obstetric Anal Sphincter Tear

Purpose This study was designed to evaluate prospectively the results of the overlap technique in primary sphincter reconstruction after obstetric tear. Methods Obstetric tears in 44 women were operated on with primary overlap reconstruction. These women were investigated six to nine months after the operation. Results were compared with those of a historical control group of 52 women whose obstetric sphincter rupture had been treated with the end-to-end technique. Results The overlap group had significantly more incontinence symptoms after delivery and repair of the sphincter tear than before delivery (P < 0.0001); however, their incontinence symptoms were significantly fewer than those of the end-to-end group (P = 0.004). The prevalence of persistent rupture of the external anal sphincter was significantly lower in the overlap group (6/44, 13.6 percent) than in the end-to-end group (39/52, 75 percent; P < 0.0001). Internal anal sphincter rupture occurred in 5 patients (11.4 percent) in the overlap group and in 40 patients (76.9 percent) in the end-to-end group (P < 0.0001). Conclusions The overlap technique should be adopted as the method of choice for primary sphincter repair after obstetric tear.     

Association of oxidative stress and PON1 with LDL and HDL particle size in middle-aged subjects

BACKGROUND: Alterations in plasma lipoprotein subclass distributions affect atherosclerosis risk. Smaller, denser low-density lipoprotein (LDL) particles (sdLDL) are more susceptible to oxidation. In contrast, most of the protective effects of high-density lipoproteins (HDL) are attributable to larger particles. This study investigates the connection between LDL and HDL particle heterogeneity and oxidative stress, antioxidative defence (AOD) and paraoxonase (PON1) status in a healthy middle-aged Serbian population. MATERIALS AND METHODS: LDL and HDL particle sizes and subclass distributions were measured by gradient gel electrophoresis in 104 men and 103 women, aged 53 +/- 9.4 years. PON1 activities and PON1(Q192R) phenotypes were determined with paraoxon and diazoxon as substrates. The oxidative stress/AOD status was estimated by measuring malondialdehyde (MDA) and superoxide-anion (O2*(-)) levels and superoxide-dismutase (SOD) activity. RESULTS: Subjects with sdLDL had significantly higher MDA (P < 0.001) and O2*(-)(P < 0.05) levels and greater diazoxonase (DZOase) activity (P < 0.05) compared to subjects with larger LDL particles. A high MDA concentration was a significant predictor of the sdLDL phenotype (P < 0.005). Increased levels of and MDA were associated with smaller HDL(3) subclass abundance. Reduced HDL particle size was associated with lower DZOase activity (P < 0.01). CONCLUSIONS: Even in the absence of symptoms of atherosclerosis, sdLDL particles are associated with increased oxidative stress, which may stimulate a compensatory rise in PON1 DZOase activity. Elevated oxidative stress may significantly affect HDL subclass distribution, resulting in the accumulation of smaller, denser HDL particles with diminished antioxidative capacity.     

The association of PC-1 (ENPP1) K121Q polymorphism with metabolic syndrome in patients with coronary heart disease

BACKGROUND: Metabolic syndrome (MS) is a clinical feature, closely associated with insulin resistance, one of the prime underlying causes of overall cardiovascular morbidity, including coronary heart disease (CHD). Considering the association between PC-1 121Q genotype and insulin resistance phenotype, the aim of the present study was to investigate the contribution of PC-1 K121Q polymorphism to the development of MS and its concomitant disorders in CHD patients. METHODS: A total of 130 Caucasians from Serbia, including 80 CHD patients (aged 59.4+/-8.6 years, of a mean BMI 28.9+/-3.9 kg/m2) and 50 control subjects (aged 48.0+/-6.4 years, of a mean BMI 29.6+/-2.1 kg/m2), were genotyped for PC-1 K121Q using a mutagenic separated PCR assay, in order to determine the prevalence of the PC 121Q variant in individuals suffering from CHD and its association with MS. RESULTS: The frequency of PC-1 121Q allele found in CHD patients was 28.5%, with significantly (P<0.01) higher prevalence in those with MS (40% vs. 10%). Both MS (P<0.01) and its components [central obesity (P<0.01), low HDL-cholesterol (P<0.01) and high triglycerides (P<0.05)] were significantly more prevalent in CHD 121Q carriers compared to CHD patients who exhibited the wild-type genotype. A binary logistic regression model has revealed that PC-1 121Q allele carriers had a 5.5 fold increased odds (95%CI: 1.4-20.9, P=0.01) for the MS compared to wild-type carriers. The PC-1 121Q allele contributed to MS components as well, although these associations did not reach statistical significance. CONCLUSION: The findings of the present study support the hypothesis that the PC-1 (ENPP1) 121Q allele is associated with the genetic susceptibility for MS in patients with CHD. Further studies and more extensive research in this area are needed, not only to confirm this association, but to elucidate it in more details.