Evaluation of erectile dysfunction and sleep-related erections

Significant advances in this past decade have improved our understanding of erectile physiology. A variety of tests are available for diagnosing impotence. SRE testing provides objective physiological information that is useful for indexing erectile capability and formulating a rational treatment plan. As such, SRE testing is a powerful noninvasive tool for assessing dysfunction. Nonetheless, in making a final diagnosis, the skillful clinician relies on more than one assessment parameter and on clinical acumen.     

Splenic artery aneurysms in liver transplant patients. Liver Transplant Group

BACKGROUND/AIMS: The purpose of the study was to investigate the incidence of and risk factors for splenic artery aneurysms in liver transplant patients. METHODS: Medical records and the pre- and 1-year postoperative angiograms of 337 liver transplant patients were reviewed to assess the presence and characteristics of these aneurysms. RESULTS: Forty-five patients with aneurysms were identified (13%): 41 cases in 242 adult patients (17%) and four (4%) in 95 children (p<0.01). The female-to-male ratio was 2:1. The majority of the aneurysms (87%) were located in the distal third of the splenic artery and the majority (87%) of the patients presented multiple aneurysms. In patients without portal hypertension no aneurysms were identified, whereas in 16% of the patients with portal hypertension aneurysms were found (p<0.001). In adult patients the incidence of splenic artery aneurysms was significantly higher in patients with parenchymal diseases than in patients with cholestatic diseases (p<0.0001). Two patients (4%) died due to rupture of the aneurysms. Control angiographies, 1 year after liver transplantation, showed no changes in size and number of the aneurysms, and no new aneurysms were identified. CONCLUSIONS: The incidence of splenic artery aneurysms in liver transplant patients is 13%. They are generally multiple and located in the distal third of the splenic artery. The incidence is higher in women and in patients with parenchymal liver disease and portal hypertension. The incidence of rupture was 4%.     

Interchain cysteine bridges control entry of progesterone to the central cavity of the uteroglobin dimer

The progesterone–binding protein uteroglobin has beenexpressed in Escherichia coli in an unfused, soluble form. likemature uteroglobin from rabbit endometrium (UG), the E.coliproduceduteroglobin (UG1) dimerizes in vitro, forms an antiparalleldimer with Cys3–Cys69' and Cys69–Cys3' disulfidebonds and binds progesterone under reducing conditions. In orderto analyze the dimerization and the reduction dependence ofprogesterone binding in more detail, we separately replacedcysteine 3 and cysteine 69 by serines. Under reducing conditions,both uteroglobin variants (UGl–3Ser and UGl–69Ser)bind progesterone with the same affinity as the wild–typesuggesting that both cysteine residues are not directly involvedin progesterone binding. In contrast to the wild–typeprotein, both cysteine variants also bind progesterone withhigh affinity in the absence of reducing agents. In addition,UGl-3Ser and UGl-69Ser both form covalently linked homodimers.Thus, unnatural Cys69–69' and Cys3–3' disulfidebonds exist in UG1–3Ser and UG1–69Ser, respectively.These data together with computer models based on X-ray diffractiondata strongly support the idea that progesterone reaches itsbinding site located in an internal hydrophobic cavity via ahydrophobic tunnel along helices 1 and 4. Under non–reducingconditions the tunnel is closed by two disulfide bridges (Cys3–Cys69'(and Cys69–Cys3') that lie in the most flexible regionof the dimer. Reduction or replacement of a cysteine residueenables conformational changes that open the channel allowingprogesterone to enter.     

Dried leaves from rocky mountain plants decrease infestation by stored-product beetles

Leaves of two highly aromatic plants,Artemisia tridentata (Nutt.) andMonarda fistulosa L., prepared according to a patented process, inhibited oviposition by the Mexican bean weevil,Zabrotes subfasciatus (Boheman), in beans at concentrations less than 1% w/w. Both plant species were less effective against the rice weevil,Sitophilus oryzae L., in wheat, with onlyM. fistulosa exhibiting any concentration-dependent activity. The maximal control achieved against this species was less than 50% at 3% w/w. Two less aromatic plant species,Balsamorhiza sagittata (Pursh.) Nutt. andGeranium viscosissimum Fisch. and Mey., caused only low levels of inhibition against both insect species. Volatiles probably caused the response toA. tridentata andM. fistulosa, while the asymptotic concentration dependence for the less volatile plant material was likely caused by behavioral factors related to the physical presence of foreign particulate matter in the foodstuff. Chemical analysis indicated that most of the volatile components from the dried leaf material from all species were terpenoids, with camphor (9.7 mg/g) and 1,8-cineole (4.0 mg/g) being most abundant inA. tridentata and carvacrol (26.3 mg/g) being most abundant inM. fistulosa.Portions of this research were conducted by the U.S. Department of Agriculture. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap. This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by USDA.     

Apoptosis of neurons in the vestibular nuclei of adult mice results from prolonged change in the external environment

Five patients with non-cytotoxic drug-induced agranulocytosis were treated with recombinant human granulocyte-colony-stimulating factor (rh-G-CSF). The drugs involved were dipyrone, captopril, clozapine and carbimazole. Bone marrow examination revealed a depleted granulopoiesis with normal erythro- and megakaryocytopoiesis. After discontinuation of the suspected drug, rh-G-CSF was administered daily at 5 microg/kg subcutaneously. The neutrophil counts were recovered between day 6 and 12 and patients were discharged from hospital shortly afterwards. Compared to data from the literature, the neutrophil recovery appeared to be faster than expected without the use of haematopoietic growth factors. In conclusion, rh-G-CSF at a standard dose of 5 microg/kg seems to be an effective treatment for drug-induced agranulocytosis.     

Tumor suppressor p16INK4A: structural characterization of wild-type and mutant proteins by NMR and circular dichroism

The tumor suppressor p16INK4A with eight N-terminal amino acids deleted (p16/delta 1-8) was expressed in Escherichia coli without any fusion artifacts and purified. The integrity of p16/delta 1-8 was confirmed by mass spectrometry, and its activity was demonstrated by in vitro cdk4 inhibition assay. Various physical methods were used to characterize the molecular and structural properties of p16/delta 1-8. The protein was found to oligomerize in vitro, as demonstrated by gel electrophoresis, mass spectrometry, and NMR. Various approaches, including changes of concentration and pH, additions of salts, detergents, and various organic solvents, and construction of a C-terminal deletion mutant and a cysteine mutant were used to try to reduce the extent of oligomerization. Only decreasing the protein concentration was found to reduce oligomerization. The affinity between p16 molecules in vivo was demonstrated by the yeast two-hybrid system. The protein was found to be very unstable on the basis of urea- and guanidinium chloride-induced denaturation studies monitored by NMR and CD, respectively. Despite these unfavorable properties, total NMR assignments were accomplished with uniform 13C and 15N isotope labeling. All multidimensional NMR experiments were performed at a very low concentration of 0.2 mM. The secondary structure was then determined from the NMR data. The results of NMR and CD studies indicate that the protein is highly alpha-helical, and the ankyrin repeat sequences show helix-turn-helix structures. This is the first structural information obtained for the important motif of ankyrin repeats. Overall, p16/delta 1-8 appears to be conformationally flexible. In order to understand the structural basis of the functional changes for some mutants existing in tumor cells, several missense mutants of p16/delta 1-8 were constructed. Four of them were expressed at high levels and purified. The molecular and structural properties of these mutants were analyzed by CD and NMR and compared with the corresponding properties of wild-type p16/delta 1-8. The results suggest that the functional changes in P114L and G101W are likely to be related to global conformational changes. In addition, we have demonstrated that the tendency of aggregation increases significantly by a single D84H mutation.     

Alkalinization prolongs recovery from glutamate-induced increases in intracellular Ca2+ concentration by enhancing Ca2+ efflux through the mitochondrial Na+/Ca2+ exchanger in cultured rat forebrain neurons

Increasing extracellular pH from 7.4 to 8.5 caused a dramatic increase in the time required to recover from a glutamate (3 microM, for 15 s)-induced increase in intracellular Ca2+ concentration ([Ca2+]i) in indo-1-loaded cultured cortical neurons. Recovery time in pH 7.4 HEPES-buffered saline solution (HBSS) was 126 +/- 30 s, whereas recovery time was 216 +/- 19 s when the pH was increased to 8.5. Removal of extracellular Ca2+ did not inhibit the prolongation of recovery caused by increasing pH. Extracellular alkalinization caused rapid intracellular alkalinization following glutamate exposure, suggesting that pH 8.5 HBSS may delay Ca2+ recovery by affecting intraneuronal Ca2+ buffering mechanisms, rather than an exclusively extracellular effect. The effect of pH 8.5 HBSS on Ca2+ recovery was similar to the effect of the mitochondrial uncoupler carbonyl cyanide p-(trifluoromethoxyphenyl)hydrazone (FCCP; 750 nM). However, pH 8.5 HBSS did not have a quantitative effect on mitochondrial membrane potential comparable to that of FCCP in neurons loaded with a potential-sensitive fluorescent indicator, 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine++ + iodide (JC-1). We found that the effect of pH 8.5 HBSS on Ca2+ recovery was completely inhibited by the mitochondrial Na+/Ca2+ exchange inhibitor CGP-37157 (25 microM). This suggests that increased mitochondrial Ca2+ efflux via the mitochondrial Na+/Ca2+ exchanger is responsible for the prolongation of [Ca2+]i recovery caused by alkaline pH following glutamate exposure.     

新国标下的氯乙烯尾气净化难点及解决方法

介绍了我国烧碱、聚氯乙烯行业大气污染物排放标准的变化,剖析了执行新国家标准(GB 15581—2016)后氯乙烯尾气净化的难点及解决方法,并列举了氯乙烯尾气净化装置改造实例。新建或改造的氯乙烯尾气净化装置,既要选择合适的工艺技术方案,又要严格遵守各项分析标准的规定,才能达到新国家标准对排放气的要求。     

The influence of the oncogenes NRAS and MYC on the radiation sensitivity of cells of a human melanoma cell line

Activation of certain oncogenes may alter the sensitivity of cells to ionizing radiation. We studied the effect of oncogene activation on the radiation sensitivity of cells of a human melanoma cell line. The cell line IGR39D was transfected with the MYC oncogene, the proto-oncogene NRAS, NRAS activated by a point mutation (61-arginine) or a combination of mutated NRAS and MYC. Single-dose experiments showed a decreased survival after transfection with MYC, wild-type NRAS or mutated NRAS. Co-transfection with MYC and mutated NRAS decreased survival up to 4 Gy, whereas at higher doses no shift in radiosensitivity was seen. Flow cytometry data indicated that differences in radiosensitivity could be explained at least in part by a difference in the distribution of cells in the phases of the cell cycle. After transfection of cells with either NRAS or MYC, the number of cells in G1 phase decreased with a concomitant increase of cells in the G2/M phase. When the cell line transfected with activated NRAS was manipulated so that the distribution of the cells in the phases of the cell cycle resembled th at of the parental line at the time of irradiation, the survival of the cells was improved. Similar experiments with the cell line containing MYC did not result in an alteration of the distribution of the cells in the cycle, or the survival after single-dose fractions, suggesting the presence of a distinct mechanism for influencing radiation sensitivity. Both NRAS and MYC transfection decrease the radiation sensitivity of human melanoma cells, but the underlying mechanisms seem different. In conclusion, transfection with NRAS or MYC alone increases radiation sensitivity while transfection of cells containing NRAS with MYC restores resistance at higher doses.     

The risk intraocular juvenile xanthogranuloma: survey of current practices and assessment of risk

BACKGROUND: Juvenile xanthogranuloma (JXG) is an uncommon, usually uncomplicated disease of childhood. Ocular involvement, however, can result in glaucoma and blindness if left untreated. The incidence of ocular complications and how best to screen for their occurrence is unknown. OBJECTIVE: We attempted to ascertain management and referral practices among ophthalmologists and dermatologists and to characterize the risk for ocular complications in children with JXG. METHODS: A total of 431 dermatologists and 438 ophthalmologists were surveyed. In addition, the literature was reviewed. RESULTS: The response rate were 28% (dermatologists) and 44% (ophthalmologists). Most believed screening was important, but referral and surveillance practices varied widely. The survey incidence of ocular complications in patients with cutaneous JXG was approximately 0.3% (7 of 2371). The literature incidence was 0.4% (1 of 260). Children at maximum risk were 2 years of age or younger, had multiple skin lesions, and had newly diagnosed JXG. CONCLUSION: Ophthalmologic screening of patients with JXG should be particularly targeted to patients with risk factors of multiple skin lesions, new diagnosis, and age of 2 years or younger.