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Although ultrasound is the primary modality used in the diagnosis of ectopic pregnancy, various forms of this condition and their complications may occasionally be further evaluated with MRI or may be incidentally detected on CT or MRI when an alternative diagnosis is suspected. Various types of ectopic pregnancy have characteristic imaging features. Radiologists should be familiar with these features and should always consider the possibility of ectopic pregnancy in the setting of hemoperitoneum or a pelvic mass in a woman of child-bearing age. Familiarity with the typical CT and MRI appearances of various forms of ectopic pregnancy facilitates prompt and accurate diagnosis and treatment. Show less

We propose a 3-layer composite closure technique for an oral antral communication (OAC) while avoiding secondary donor site morbidity. A patient had developed a 1-cm OAC after extraction of right maxillary first molar. The patient subsequently developed acute maxillary sinusitis. The patient was taken to the operating room, and a Caldwell-Luc procedure was performed. The bony window from the Caldwell-Luc was "press fit" over the bony OAC defect. Soft tissue closure was then achieved with a buccal fat pad flap and a buccal mucosal advancement flap. The patient was examined on postoperative day 5 and 1, 2, 3, 6, and 10 months postoperatively. The acute sinusitis had resolved. The soft tissue closure was successful. The bone graft remained intact, prevented sinus pneumatization, and restored continuity to the floor of the maxillary sinus. The presented technique for 3-layer closure of OACs allows for the stability of a double-layer closure of OAC with the added benefit of bone grafting from single operative site, achieving stable oral antral closure, bone grafting, and the avoidance of secondary donor site morbidity. Show less

Dyggve-Melchior-Clausen syndrome (DMC) (MIM #223800) is a rare autosomal-recessive type of skeletal dysplasia accompanied by variable degrees of intellectual disability (ID). It is characterized by progressive spondyloepimetaphyseal dysplasia leading to disproportionate short stature, microcephaly, and coarse facies. The radiographic appearance of generalized platyspondyly with double-humped end plates and the lace-like appearance of iliac crests are pathognomonic in this syndrome. The disorder results from mutations in the dymeclin (DYM) mapped to the 18q12-12.1 chromosomal region. Here, we report two cases with DMC: one with disproportionate short stature, developmental delay, and severe ID with a novel frameshift mutation (c.1028₁₀₅₆del29) leading to a premature stop codon, and the second patient with classical clinical and radiological features of DMC with mild ID and rectal prolapse, which is very rare. The clinical diagnosis was confirmed with molecular analysis of DYM with a known mutation at c.580C>T (p.R194X). The parents and sibling of the second patient were heterozygous carriers with mild skeletal changes and short stature. Show less

Studies on spermatogonial stem cells (SSCs) are of unusual significance because they are the unique stem cells that transmit genetic information to subsequent generations and they can acquire pluripotency to become embryonic stem-like cells that have therapeutic applications in human diseases. MicroRNAs (miRNAs) have recently emerged as critical endogenous regulators in mammalian cells. However, the function and mechanisms of individual miRNAs in regulating SSC fate remain unknown. Here, we report for the first time that miRNA-20 and miRNA-106a are preferentially expressed in mouse SSCs. Functional assays in vitro and in vivo using miRNA mimics and inhibitors reveal that miRNA-20 and miRNA-106a are essential for renewal of SSCs. We further demonstrate that these two miRNAs promote renewal at the post-transcriptional level via targeting STAT3 and Ccnd1 and that knockdown of STAT3, Fos, and Ccnd1 results in renewal of SSCs. This study thus provides novel insights into molecular mechanisms regulating renewal and differentiation of SSCs and may have important implications for regulating male reproduction. Show less

The optimal strategy for inducing fertility in men with congenital hypogonadotropic hypogonadism (CHH) is equivocal. Albeit a biologically plausible approach, pretreatment with recombinant FSH (rFSH) before GnRH/human chorionic gonadotropin administration has not been sufficiently assessed. The objective of the study was to test this method. This was a randomized, open-label treatment protocol at an academic medical center. GnRH-deficient men (CHH) with prepubertal testes (<4 mL), no cryptorchidism, and no prior gonadotropin therapy were randomly assigned to either 24 months of pulsatile GnRH therapy alone (inducing endogenous LH and FSH release) or 4 months of rFSH pretreatment followed by 24 months of GnRH therapy. Patients underwent serial testicular biopsies, ultrasound assessments of testicular volume, serum hormone measurements, and seminal fluid analyses. rFSH treatment increased inhibin B levels into the normal range (from 29 ± 9 to 107 ± 41 pg/mL, P < .05) and doubled testicular volume (from 1.1 ± 0.2 to 2.2 ± 0.3 mL, P < .005). Histological analysis showed proliferation of both Sertoli cells (SCs) and spermatogonia, a decreased SC to germ cell ratio (from 0.74 to 0.35), and SC cytoskeletal rearrangements. With pulsatile GnRH, the groups had similar hormonal responses and exhibited significant testicular growth. All men receiving rFSH pretreatment developed sperm in their ejaculate (7 of 7 vs 4 of 6 in the GnRH-only group) and showed trends toward higher maximal sperm counts. rFSH pretreatment followed by GnRH is successful in inducing testicular growth and fertility in men with CHH with prepubertal testes. rFSH not only appears to maximize the SC population but also induces morphologic changes, suggesting broader developmental roles. Show less

Bisdemethoxycurcumin (BDMC) is a natural derivative of curcumin present in the phenolic components extracted from the dried rhizome of Curcuma longa L. BDMC demonstrated potential chemotherapeutic activities but the underlying mechanisms have not been fully clarified. In the present study, the role of reactive oxidative species (ROS) in the anti-cancer effects of BDMC was investigated. MCF-7 cells were exposed to BDMC, and then the cell proliferation, colony formation ability and cell cycle profile were analyzed. Cellular ROS level was determined by flow cytometry and fluorescent microscope observation using specific fluorescent probes. Mitochondrial membrane potential (ψm) was assessed using JC-1. In addition, effects of BDMC on senescence-related molecules were analyzed by western blot assay. BDMC significantly inhibited MCF-7 breast cancer cell proliferation, while a rapid rise of the intracellular ROS level accompanied with a reduction of Dym were observed. In addition, BDMC activated the pro-apoptotic protein p53 and its downstream effector p21 as well as the cell cycle regulatory proteins p16 and its downstream effector retinoblastoma protein (Rb). All of these BDMC-induced effects were counteracted with the pre-incubation of the antioxidant N-acetylcysteine (NAC). These results suggested that BDMC-induced ROS accumulation may contribute to its inhibitory effect on MCF-7 cell viability through regulation of p53/p21 and p16/Rb pathways. Show less

Follicular lymphoid hyperplasia of the palate is a benign lymphoproliferative lesion of unknown pathogenesis. It presents usually in female patients as a painless, firm, well-demarcated, usually nonulcerated, slow-growing lesion on the palate that histopathologically may resemble a lymphoma. The authors describe a patient with this condition that was successfully treated with intralesional steroid injections. Previously reported cases were reviewed to assess the results of various treatment modalities and disease-free outcome. A nonsurgical approach to the management of follicular lymphoid hyperplasia may have better patient acceptance and satisfaction without recurrence. Show less

Chronic lymphocytic leukemia (CLL) remains incurable; therefore searching for new therapeutic strategies in this disease is necessary. An important mechanism of tumor development is neoangiogenesis. A potent antiangiogenic factor, bevacizumab (Avastin, AVA), has been poorly explored in CLL so far. In the current study we assessed cytotoxic activity of AVA alone or in combinations with drugs routinely used in this disease. Cells isolated from 60 CLL patients were treated with AVA alone or in combination with anti-CD20 monoclonal antibody (MoAb), rituximab (RIT), anti-CD52 MoAb, alemtuzumab (ALT), 2-CdA (2-chlorodeoxyadenosine), FA (fludarabine), MAF (mafosfamide) or RAPA (rapamycin). Cytotoxicity was assessed by propidium iodide staining. Apoptosis was evaluated using annexin-V and TUNEL assays. Additionally, a drop of mitochondrial potential (DYm) as well as expression of apoptosis-regulating proteins Bax, Bak, Bid, Bad, Bcl-2, Mcl-2, XIAP, FLIP, Akt and Bcl-2-A1 were determined by flow cytometry. At the dose of 40 μg/ml, after 48 hours of incubation, AVA induced significant cytotoxicity against CLL cells. The drug triggered apoptosis, with activation of caspase-3 and -9, but not caspase-8, along with a drop of DYm. Incubation with AVA induced significant overexpression of proapoptotic Bak and Bad as well as downregulation of antiapoptotic Mcl-2 and Akt proteins. Combination of AVA with RIT, ALT or RAPA significantly increased cytotoxicity when compared with the effects of single drugs. In conclusion, this is the first report showing proapoptotic activity of AVA against CLL cells. Combination of AVA with RIT, ALT or RAPA may be a promising therapeutic strategy, which requires confirmation in further studies. Show less

Understanding the extent of genomic transcription and its functional relevance is a central goal in genomics research. However, detailed genome-wide investigations of transcriptome complexity in major mammalian organs have been scarce. Here, using extensive RNA-seq data, we show that transcription of the genome is substantially more widespread in the testis than in other organs across representative mammals. Furthermore, we reveal that meiotic spermatocytes and especially postmeiotic round spermatids have remarkably diverse transcriptomes, which explains the high transcriptome complexity of the testis as a whole. The widespread transcriptional activity in spermatocytes and spermatids encompasses protein-coding and long noncoding RNA genes but also poorly conserves intergenic sequences, suggesting that it may not be of immediate functional relevance. Rather, our analyses of genome-wide epigenetic data suggest that this prevalent transcription, which most likely promoted the birth of new genes during evolution, is facilitated by an overall permissive chromatin in these germ cells that results from extensive chromatin remodeling. Show less

Dyggve-Melchiore-Clausen (DMC) syndrome is a are autosomal recessive spondyloepimetaphyseal dysplasia associated with mental retardation resulting from mutations in the Dymeclin (DYM) gene mapped in the 18q12-12.1 chromosomal region. We report a case of a consanguineous Moroccan boy with this disease confirmed by the presence of homozygous mutation at c.1878delA of DYM gene. Our patient additionally has a micropenis. We discuss the clinical severity, difficult management of this syndrome and its association with micropenis never described before in the literature. Show less

To determine the feasibility of using gadoxetate disodium for MR urography. We retrospectively reviewed 50 consecutive gadoxetate disodium-enhanced abdominal MRI examinations meeting inclusion criteria. For each examination, 30 min postcontrast hepatobiliary phase sequences were reviewed to assess bilateral collecting system segments, including upper pole, interpolar, and lower pole calyces; renal pelvis; and proximal one-third of ureter. Each segment was assessed for degree of opacification (none, <50%, ≥50%, complete) and susceptibility artifact (none, partial thin rim, thick/complete rim, total obscuration). Opacification and susceptibility scores were also calculated for each examination. The 50 reviewed examinations were performed on 46 patients (26 women, 20 men; mean age, 57 years) and included a total of 1000 segments. Of these, 808 (80.8%) were opacified completely, 103 (10.3%) were opacified ≥50%, 39 (3.9%) were opacified <50%, and 50 (5.0%) were not opacified. Of 1000 segments, no susceptibility artifact was present in 822 (82.2%), while a partial thin rim was present in 113 (11.3%), a thick/complete rim in 64 (6.4%) and total obscuration in 1 (0.1%). Gadoxetate disodium contrast produced a high degree of opacification of the proximal urinary collecting system with low incidence of susceptibility artifact; therefore, it is a feasible contrast agent for MR urography. Show less

Diaminopimelate aminotransferase (DAP-AT) is an enzyme in the lysine-biosynthesis pathway. Conversely, ALD1, a close homologue of DAP-AT in plants, uses lysine as a substrate in vitro. Both proteins require pyridoxal-5'-phosphate (PLP) for their activity. The structure of ALD1 from the flowering plant Arabidopsis thaliana (AtALD1) was solved at a resolution of 2.3 Å. Comparison of AtALD1 with the previously solved structure of A. thaliana DAP-AT (AtDAP-AT) revealed similar interactions with PLP despite sequence differences within the PLP-binding site. However, sequence differences between the binding site of AtDAP-AT for malate, a purported mimic of substrate binding, and the corresponding site in AtALD1 led to different interactions. This suggests that either the substrate itself, or the substrate-binding mode, differs in the two proteins, supporting the known in vitro findings. Show less

The purpose of the research was to study kindergarteners' exposition to environmental tobacco smoke (ETS) in houses. Social and economical factors were checked for the improper behavior of grown-up household. Material for the research were data collected from questionnaires filled by children's parents. 272 three years old children were studied (57.7% boys and 42.3% girls). Cotinine--marker of exposition to ETS was measured in the children's urine. In 32.4% houses at least one resident was a tobacco smoker. The most often it was father (22.3%) or mother (10.6%). Most of them (78.7%) affirmed tobacco smoking out of houses. Tobacco smoking correlated to parents education (mothers--college graduate and fathers--high-school graduate smoked tobacco the most often). Tobacco smoking by the parents correlated to low household income (less than 1000 zl), many house occupants (4-5 persons), small house area (less than 15 m2/person). A part of studied group of children (11%) was exposed to ETS out of house. Mean cotinine concentration in urine of children exposed and unexposed to ETS in house were not significantly different an were respectively: 25.60 and 21.22 ng/mg creatinine. Propagation of right behavior among people smoking tobacco in houses and education of small children parents is important. Show less

Gallbladder torsion is a rare cause of acute gangrenous cholecystitis; its occurrence within an abdominal hernia has not been previously reported. We present such a case occurring within a parastomal hernia and imaged with unenhanced CT. Show less

Smith-McCort dysplasia (SMC) is a rare autosomal recessive spondylo-epi-metaphyseal dysplasia with skeletal features identical to those of Dyggve-Melchior-Clausen syndrome (DMC) but with normal intelligence and no microcephaly. Although both syndromes were shown to result from mutations in the DYM gene, which encodes the Golgi protein DYMECLIN, a few SMC patients remained negative in DYM mutation screening. Recently, autozygosity mapping and exome sequencing in a large SMC family have allowed the identification of a missense mutation in RAB33B, another Golgi protein involved in retrograde transport of Golgi vesicles. Here, we report a novel RAB33B mutation in a second SMC case that leads to a marked reduction of the protein as shown by Western blot and immunofluorescence. These data confirm the genetic heterogeneity of SMC dysplasia and highlight the role of Golgi transport in the pathogenesis of SMC and DMC syndromes. Show less

The purpose of this study is to determine the proficiency of emergency medicine residents in selecting appropriate radiologic examinations for specific clinical scenarios and to ascertain whether their training improves competency in this area over the course of their residency. An online multiple-choice questionnaire was created. It included 10 clinical scenarios excerpted from the American College of Radiology Appropriateness Criteria guidelines and instructed residents to select the most appropriate initial imaging study. A link and invitation to the survey were e-mailed to the residency program directors and coordinators of all American Council for Graduate Medical Education-accredited emergency medicine residency training programs with the request that they be forwarded to their current residents. Responses were graded, with correct answers derived from the American College of Radiology guidelines. Results were stratified by year of emergency medicine training, and an analysis of variance was performed. A total of 583 residents from at least 77 different emergency medicine residency training programs completed the survey. Overall, the average number of questions answered correctly was 7.1 of 10 (SD, 1.2). First-through fourth-year residents averaged 6.9 (SD, 1.3), 7.1 (SD, 1.2), 7.1 (SD, 1.1), and 7.5 (SD, 1.1) correct answers, respectively. Analysis of variance found no significant difference between the scores of the four classes (p = 0.09). Emergency medicine residents do not show significant improvement over the course of their residency in their ability to choose appropriate imaging studies. This finding suggests that there is a role for more-rigorous focused instruction to better familiarize residents with appropriateness guidelines for diagnostic imaging selection. Show less

This article is devoted to risk-management strategies regarding oral surgical procedures in the general dental office. Lawsuits are more likely to be filed following poor outcomes related to oral surgical procedures rather than after operative or prosthetic dental procedures. The article is not meant to discourage practitioners from performing oral surgical procedures if they have the experience, training, and appropriate skill set to complete the planned procedure. Rather, it advises clinicians as to the steps one can take to limit the chances of litigation from occurring, and avoid the emotionally and painful time-consuming process associated with a malpractice lawsuit. Show less

Dyggve--Melchior--Clausen syndrome (DMC) is a chondrodysplasia that bears significant phenotypic resemblance to mucopolysaccharidosis type IV (Morquio disease). Autosomal recessive mutations in DYM are known to cause this disease through its role in Golgi organisation and intracellular traffic, but genetic heterogeneity is suspected. A family with DMC and normal intellectual development underwent clinical evaluation followed by autozygosity mapping and exome sequencing. Immunoblot and immunofluorescence analyses were performed to characterise the effect of the mutation. This multiplex consanguineous family links to a novel locus on 4q31.1. Exome sequencing revealed a missense mutation in RAB33B, which encodes a Rab protein with an established role in retrograde Golgi traffic. The mutation qualitatively replaces the invariant lysine residue in the guanine nucleotide-binding domain of this small GTPase protein and leads to marked protein deficiency, making it the likely causative mutation of DMC in this family. This study identifies a new DMC gene and highlights the role of intracellular traffic in the pathogenesis of this disease. Show less

Extraction of impacted teeth is one of the most common surgical procedures performed by oral and maxillofacial surgeons. Every surgical procedure results in some degree of postoperative bleeding and inflammation, typically manifesting as pain and edema. Although the complex physiology of the human body is beyond the scope of this article, the educated clinician should have an understanding of the time line associated with these processes so as to determine whether a patient's complaint of postoperative bleeding, pain, or swelling represents a normal response to surgical trauma or an aberrant reaction. Show less

In recent years, the increase in the incidence of multiple sclerosis (MS - Multiple Sclerosis) is observed. and the direct cause of the symptoms of multiple sclerosis is myelin nerves damage. It can be concluded that the environmental factor is at least partly responsible for the occurrence of this disease. For the development of this disease are responsible, in addition to genetic factors, compounds present in many parts of the environment. Many of these compounds may adversely affect the redox equilibrium of the body, exacerbating radicalgenesis and decreasing antioxidant defenses. Multiple sclerosis is usually diagnosed in early adulthood, during most daily activities. Effects of SM on living standards includes not only the medical aspect, but also social, economic and emotional aspect. Polish population is a high risk zone regarding multiple sclerosis. The aim of this study was a preliminary assessment of selected environmental exposure factors in the pathogenesis of multiple sclerosis with regard to exposure to tobacco smoke with the author's survey of patients from the region of Upper Silesia. Most MS patients (32) in the study group (suffering from MS from 2 to 44 years) are inhabitants of agglomeration of over 50 thousand citizens, from the area of Gliwice, Bytom and Zabrze (43.75%). In investigated group 46.88% MS patients from Silesia region were exposed to tobacco smoke, of which 21.88% actively smoke. Patients with MS, in order not to worsen their disease manifestation, should stop smoking and increase, if possible, any physical activities. These data will be incorporated into a wide-ranging research to clarify the role of selected environmental factors in a very complex and still not fully explored the pathogenesis of multiple sclerosis in Upper Silesia. Show less

Ischemic stroke is a devastating disease with a complex pathophysiology. Galangin is a natural flavonoid isolated from the rhizome of Alpina officinarum Hance, which has been widely used as an antioxidant agent. However, its effects against ischemic stroke have not been reported and its related neuroprotective mechanism has not really been explored. In this study, neurological behavior, cerebral infarct volumes and the improvement of the regional cortical blood flow (rCBF) were used to evaluate the therapeutic effect of galangin in rats impaired by middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia. Furthermore, the determination of mitochondrial function and Western blot of apoptosis-related proteins were performed to interpret the neuroprotective mechanism of galangin. The results showed that galangin alleviated the neurologic impairments, reduced cerebral infarct at 24 h after MCAO and exerted a protective effect on the mitochondria with decreased production of mitochondrial reactive oxygen species (ROS). These effects were consistent with improvements in the membrane potential level (Dym), membrane fluidity, and degree of mitochondrial swelling in a dose-dependent manner. Moreover, galangin significantly improved the reduced rCBF after MCAO. Western blot analysis revealed that galangin also inhibited apoptosis in a dose-dependent manner concomitant with the up-regulation of Bcl-2 expression, down-regulation of Bax expression and the Bax/Bcl-2 ratio, a reduction in cytochrome c release from the mitochondria to the cytosol, the reduced expression of activated caspase-3 and the cleavage of poly(ADP-ribose) polymerase (PARP). All these data in this study demonstrated that galangin might have therapeutic potential for ischemic stroke and play its protective role through the improvement in rCBF, mitochondrial protection and inhibiting caspase-dependent mitochondrial cell death pathway for the first time. Show less

The practicing oral and maxillofacial surgeon treating patients with oroantral communication (OAC)/oroantral fistulas should be familiar and competent with the various treatment options available. Multiple techniques are available from purely soft tissue flaps, which have proved to be successful over time, to a combination of hard tissue grafts (autologous, alloplastic, or allograft), which can prove to be useful with the increased demand for implant restorations. Although different procedures have proved to be successful, all are premised on the treatment of any underlying sinusitis, which is associated with a higher risk of recurrent OAC. Show less

Smoking cigarettes and alcohol addiction are serious problems in health hazard and life of society. Tobacco smoke leads to many kinds of cancer formation and scientific research indicates, that heart-vascular disease and lung cancer are the most common diseases caused by tobacco smoke. While talking about ethanol, it is responsible for liver, pancreas, mucous membrane damage and leads to central and circular nervous disorder. Scientific research indicates, that many smokers drink alcohol and vice versa. Unfortunately in that case the risk of many diseases increases. Both of these stimulants leads to enlarged production of reactive oxygen species, which is connected with unbalance between pro and antioxidant processes in human organism. Free radicals in normal conditions plays positive role but with tobacco smoke and alcohol connection may lead to serious changes in human organism. They damage organs, it comes to protein structure, nucleic acid and fat violation, which in consequence leads to immunity decrease and many pathological changes. Reactive oxygen species also plays role in pathogenesis of many diseases: diabetes mellitus, atherosclerosis and Down syndrome. ROS may also increase the risk of pancreas, lung, larynx and urinary bladder cancer formation. Human organism defends oneself from harmful influence of reactive oxygen species owing to enzymatic and non-enzymatic systems presence-Non-enzymatic antioxidants: glutathione, carotene, bilirubin, tocopherol, uric acid and ions metals temporary complex belong to non-enzymatic systems. To enzymatic ones belong: catalase, superoxide dismutase, glutathione reductase and glutathione peroxidase. The aim of the study was tobacco smoke and ethyl alcohol influence evaluation in rats addicted to these substances on activity of chosen enzymes responsible for organism defense against toxic compounds action. To this study 63 white, Wistar tribe rats at the age of 3,5 months were used - males addicted to ethyl alcohol. They were divided into 3 groups, each consist of 21 rats. Animals of Group I were exposed on harmful tobacco smoke influence. Group II constitute animals, which were given by stomach probe 10% alcohol dilution once at a dose of 2 g/kg weight. The next Group - III, in which animals at first were exposed on tobacco smoke influence. When exposition was over, animals were given by stomach probe 10% alcohol dilution once at a dose of 2 g/kg weight. Depending on the type of marker and studied organ, changes in the levels of selected enzymes, responsible for defending organism against reactive forms of oxygen has been shown. Both tobacco smoke and ethyl alcohol resulted in a change of glutathione levels in the serum and tissues of animals. Tobacco smoke has the biggest influence on protein nitrozylation in the brain and ethyl alcohol had influence on glutathione level in serum, kidney, brain and superoxide dismutase activity in the brain. Application of many oxidative stress markers allows for evaluation of its differential influence on various organs. Show less

Negative attitudes in health such as cigarette smoking and imbalanced diet play important role in pathogenesis of various diseases. Cigarette smoking constitutes one of the main sources of exposure to cancerogenic and procancerogenic xenobiotics among adults as well as among young people. Many studies have proven that cigarettes smokers more frequently follow less varied diet in comparison to non-smokers. Despite increasing knowledge of Poles regarding harmful effects of cigarettes smoking and numerous antinicotine campaigns, still high number of women and men smoke and the smoking percentage among young people remains high and has not decreased in the recent years. The ongoing research shows that free radicals -the man cause of exposure to oxidative stress- play the seminal role in pathogenesis of civilisation diseases and physiological cell aging processes. Reactive oxygen and nitrogen species present in cigarette smoke due to induced toxic compounds formation, are closely connected with observed increased risk of cancer, Chronic Obstructive Pulmonary Disease (COPD) and arteriosclerosis incidents. Malondialdehyde is one of the most studied product of lipid peroxidation and biomarker of oxidative stress. However, 3-nitrotyrosine is one of the most promising biomarkers regarding changes caused by oxidative stress in living organisms. The presence of 3-nitrotyrosine was observed in many diseases such as coronary artery disease, cancer and diabetes. The aim of the study was the evaluation of free radical processes increase related to tobacco smoke exposure and chosen diet habits by determination of 3-nitrotyrosine in plasma samples collected from the group of medicine students. In our investigation we used an author's questionnaire which served to estimate the exposure to tobacco smoke among medicine students. It took also into account the knowledge of the exposure to other xenobiotics and unhealthy habits/behaviours. The investigated group included 150 students of 1-st and 2-nd year of study at Faculty of Medicine and Dentistry Division in Zabrze, Silesian Medical University. 120 students provided blood samples for further analysis. In the study group 52 students were active smokers and the control group consisted of 68 non-smokers. 3-nitrotyrosine was determined with the use of ELISA technique. The mean concentration of 3-nitrotyrosine was higher in the group of smoking students in comparison to the control group. Diet habits also influenced the concentration of 3-nitrotyrosine. Eating food products of possibly high acrylamide level and drinking alcohol led in particular to observed increased concentrations of 3-nitrotyrosine in both students groups. The correlation between the food habits and the severity of nitrosative stress was also found. Show less

Sugar appetite is influenced by unlearned attractions to sweet taste and learned responses to sugars' taste and post-ingestive actions. In rats, sugar-conditioned flavor preferences (CFP) are attenuated by dopamine D1 (SCH23390: SCH), but not by opioid (naltrexone: NTX), receptor antagonism. Sucrose-CFP occurs in BALB/c and SWR inbred mice that differ in their suppressive effects of SCH and NTX on sucrose intake. The present study examined whether SCH and NTX altered expression of previously learned sucrose-CFP and acquisition (learning) of sucrose-CFP in these strains. In Experiment 1, food-restricted mice were trained (10 one-bottle sessions) to drink a more-preferred flavored (e.g., cherry) 16% sucrose solution (CS+/Sucrose) on odd-numbered days, and a less-preferred flavored (e.g., grape) 0.05% saccharin solution (CS-/Saccharin) on even-numbered days. Two-bottle tests with the flavors mixed in 0.2% saccharin occurred 30 min following vehicle (Veh), SCH (50-800 nmol/kg) or NTX (1-5mg/kg) assessing preference expression. CS+ preference expression in BALB/c and SWR mice following Veh were significantly reduced by SCH and NTX. In Experiment 2, separate groups of BALB/c and SWR mice received Veh, SCH (50 nmol/kg) or NTX (1mg/kg) injections 30 min prior to daily one-bottle training sessions with the CS+/Sucrose and CS-/Saccharin solutions assessing preference acquisition. Subsequent two-bottle tests with the CS+ vs. CS- solutions were conducted without injections. CS+/Sucrose training intakes were reduced by SCH in both strains and by NTX in BALB/c mice. In the initial two-bottle test, sucrose-CFP acquisition was significantly reduced in BALB NTX (54%), but not in BALB SCH (77%) groups relative to the BALB Veh group (85%). In contrast, sucrose-CFP acquisition was significantly reduced in SWR SCH (61%), but not in SWR NTX (83%) groups relative to the SWR Veh group (86%). DA D1 and opioid receptor signaling modulate acquisition and/or expression of sucrose-CFP in mice with significant strain differences observed. Show less

During normal development primordial germ cells (PGCs) derived from the epiblast are the precursors of spermatogonia and oogonia. In culture, PGCs can be induced to dedifferentiate to pluripotent embryonic germ (EG) cells in the presence of various growth factors. Several recent studies have now demonstrated that spermatogonial stem cells (SSCs) can also revert back to pluripotency as embryonic stem (ES)-like cells under certain culture conditions. However, the potential dedifferentiation of SSCs into PGCs or the potential generation of oocytes from SSCs has not been demonstrated before. We report that mouse male SSCs can be converted into oocyte-like cells in culture. These SSCs-derived oocytes (SSC-Oocs) were similar in size to normal mouse mature oocytes. They expressed oocyte-specific markers and gave rise to embryos through parthenogenesis. Interestingly, the Y- and X-linked testis-specific genes in these SSC-Oocs were significantly down-regulated or turned off, while oocyte-specific X-linked genes were activated. The gene expression profile appeared to switch to that of the oocyte across the X chromosome. Furthermore, these oocyte-like cells lost paternal imprinting but acquired maternal imprinting. Our data demonstrate that SSCs might maintain the potential to be reprogrammed into oocytes with corresponding epigenetic reversals. This study provides not only further evidence for the remarkable plasticity of SSCs but also a potential system for dissecting molecular and epigenetic regulations in germ cell fate determination and imprinting establishment during gametogenesis. Show less

Disease of the teeth and their support structures is common and frequently seen at imaging of the head and neck. Recognition of dental disease by the interpreting radiologist has the potential to alter the course of patient care, such as when periapical disease is identified as the cause of sinusitis or pericoronitis is identified as the cause of deep neck infection. Furthermore, incidental recognition of carious lesions in both children and adults who are undergoing CT for other reasons may alert the patient and care team of the need for a dental consultation. In fact, most of the images of dental and periodontal conditions that are used in this article were obtained from CT studies that were performed to investigate other problems. Familiarity with the imaging appearance of common dental conditions, such as hyperdontia and hypodontia, tooth trauma, periodontal disease, caries, periapical disease, odontogenic sinusitis, and deep neck infections, allows the radiologist to render a timely, confident, and specific diagnosis of dental abnormalities, even when such findings are unexpected. Show less

Computational design is a test of our understanding of enzyme catalysis and a means of engineering novel, tailor-made enzymes. While the de novo computational design of catalytically efficient enzymes remains a challenge, designed enzymes may comprise unique starting points for further optimization by directed evolution. Directed evolution of two computationally designed Kemp eliminases, KE07 and KE70, led to low to moderately efficient enzymes (k(cat)/K(m) values of ≤ 5 10(4) M(-1)s(-1)). Here we describe the optimization of a third design, KE59. Although KE59 was the most catalytically efficient Kemp eliminase from this design series (by k(cat)/K(m), and by catalyzing the elimination of nonactivated benzisoxazoles), its impaired stability prevented its evolutionary optimization. To boost KE59's evolvability, stabilizing consensus mutations were included in the libraries throughout the directed evolution process. The libraries were also screened with less activated substrates. Sixteen rounds of mutation and selection led to > 2,000-fold increase in catalytic efficiency, mainly via higher k(cat) values. The best KE59 variants exhibited k(cat)/K(m) values up to 0.6 10(6) M(-1)s(-1), and k(cat)/k(uncat) values of ≤ 10(7) almost regardless of substrate reactivity. Biochemical, structural, and molecular dynamics (MD) simulation studies provided insights regarding the optimization of KE59. Overall, the directed evolution of three different designed Kemp eliminases, KE07, KE70, and KE59, demonstrates that computational designs are highly evolvable and can be optimized to high catalytic efficiencies. Show less