Synthesis and acid ionization constants of cyclic cystine peptides

Cyclic peptide disulfides of the general formula were synthesized from the corresponding peptide derivatives [Boc-Cys(Trt)(Gly)-_n-Cys(Trt)-OBu^t] by oxidation with iodine in methanol and by subsequent removal of the terminal groups with trifluoroacetic acid. Acid ionization constants of the obtained peptides were determined by potentiometric titration in aqueous KCl (0.1 mol/L) medium. All compounds have two dissociable hydrogens, corresponding to carboxyl (pK¹= 2.35–2.84) and to terminal amino group (pK₂= 5.61–6.93); pK₁, values show first an upward and then a downward trend with the increase in ring size; the opposite is true for pK₂, values. These trends could be tentatively attributed to the intramolecular salt bridge (-COO——-NH⁺₃-) formation.     

Epistaxis: vascular anatomy, origins, and endovascular treatment

Embolization can play an important role in controlling epistaxis. However, one must be careful to avoid nontarget embolization via the dangerous anastomoses between the ECA branches, the carotid siphon, and ophthalmic arteries.     

Counseling Fathers (2010) by C.Z. Oren and D.C. Oren

No abstract available for this article.     

A GCH1 haplotype confers sex‐specific susceptibility to pain crises and altered endothelial function in adults with sickle cell anemia

GTP cyclohydrolase (GCH1) is rate limiting for tetrahydrobiopterin (BH4) synthesis, where BH4 is a cofactor for nitric oxide (NO) synthases and aromatic hydroxylases. GCH1 polymorphisms are implicated in the pathophysiology of pain, but have not been investigated in African populations. We examined GCH1 and pain in sickle cell anemia where GCH1 rs8007267 was a risk factor for pain crises in discovery (n = 228; odds ratio [OR] 2.26; P = 0.009) and replication (n = 513; OR 2.23; P = 0.004) cohorts. In vitro, cells from sickle cell anemia subjects homozygous for the risk allele produced higher BH4. In vivo physiological studies of traits likely to be modulated by GCH1 showed rs8007267 is associated with altered endothelial dependent blood flow in females with SCA (8.42% of variation; P = 0.002). The GCH1 pain association is attributable to an African haplotype with where its sickle cell anemia pain association is limited to females (OR 2.69; 95% CI 1.21–5.94; P = 0.01) and has the opposite directional association described in Europeans independent of global admixture. The presence of a GCH1 haplotype with high BH4 in populations of African ancestry could explain the association of rs8007267 with sickle cell anemia pain crises. The vascular effects of GCH1 and BH4 may also have broader implications for cardiovascular disease in populations of African ancestry. Am. J. Hematol. 89:187–193, 2014. © 2013 Wiley Periodicals, Inc.     

Insulin receptor number and binding affinity in newborn dogs

The insulin resistance in newborn mammals may be caused by a receptor or postreceptor defect. Although liver and umbilical cord blood monocytes have increased numbers of insulin receptors, there is a paucity of information about other neonatal tissues. Glucose disposal takes place primarily in the skeletal muscle; therefore, it is important to evaluate this tissue for an insulin receptor defect. To determine the role of insulin receptors in neonatal insulin resistance, neonatal and adult canine skeletal muscle, heart, and liver were compared for numbers of insulin receptors and their affinity for insulin. Partially purified receptors from four animals in each group were obtained by wheat germ lectin affinity chromatography and used in competition binding studies. Specific binding (mean +/- SE) in the absence of cold insulin was increased in newborn skeletal muscle (9.7 +/- 0.8 versus 4.8 +/- 0.5%, p less than 0.001) and heart (8.1 +/- 1.2 versus 5.5 +/- 0.6%, p less than 0.05). High-affinity insulin receptor number (mean +/- SEM) was increased in newborn skeletal muscle (183 +/- 40 versus 120 +/- 29 pM, p less than 0.002) and heart (264 +/- 94 versus 157 +/- 51 pM, p less than 0.05) as estimated from the X intercept of the Scatchard plot. Using half-maximal binding to estimate affinity, there were no differences between adults and newborns among all tissues studied. High-affinity receptor number and percentage of specific binding were similar for newborn and adult liver tissue.(ABSTRACT TRUNCATED AT 250 WORDS)     

提高孕产期保健质量是降低贫困地区壮族妇女孕产妇死亡的有力措施

目的 :提高贫困地区壮族农村住院分娩率 ,加强产时保健 ,提高贫困地区壮族农村产科质量 ,降低产后出血死亡率。在广西 30个老少边山穷地区 ,以项目和“母亲安全工程”为载体 ,在经济条件困难 ,基础设施落后 ,围产保健服务管理滞后的情况下 ,积极贯彻落实《母婴保健法》,依法规范围产保健服务管理 ,多方筹措资金 ,加强产科软、硬件建设 ,以项目工作为龙头 ,以科研为先导 ,积极推广适宜技术。以健康促进为目的 ,大力开展健康教育和生殖保健活动 ,使围产保健工作取得了较好成绩。30个贫困地区壮族农村近半数以上乡卫生院产科建设已达自治区标准 ,基本能满足贫困地区农民住院分娩的需求 ,并带动广西妇幼卫生工作的发展