N-methylation of diamino-substituted macrocyclic complexes: Intramolecular cyclisation

Two new macropolycyclic hexaamines L(2) and L(4) as their copper(II) complexes have been isolated as products from the condensation of the diamino-substituted macrocyclic complex trans-(6,13-dimethyl-1,4,8,11-tetraazacyclo-tetradecane-6,13-diamine)copper(II) [CuL(1)](2+) with aqueous formaldehyde. Both of the complexes exhibit methylene bridges between the pendant amine and the adjacent co-ordinated macrocyclic N-donors. Their crystal structures have been determined: [CuL(2)(NCS)][SCN], triclinic, space group P (1) over bar, a = 7.133(2), b = 9.813(2), c = 16.745(3) Angstrom, alpha = 101.05(2), beta = 99.36(2), gamma = 99.77(2)degrees, Z = 2; [CuL(4)Cl][ClO4]. H2O, triclinic, space group P (1) over bar, a = 9.3327(8), b = 10.8989(6), c = 12.672(1) Angstrom, alpha = 68.591(6), beta = 78.899(6), gamma = 87.384(6)degrees, Z = 2. The complexes exhibit square-pyramidal geometries, and significantly lower-energy electronic maxima relative to their parent complex [CuL(1)](2+). Electrochemistry of [CuL(2)](2+) revealed a reversible Cu-II-Cu-I redox couple, by contrast to those of macromonocyclic analogues.

Gold(III) template synthesis of a pendant-arm macrocycle

Gold(III)-directed condensation of ethane-1,2-diamine with nitroethane and formaldehyde yielded the gold-coloured macrocyclic complex (cis-6,13-dimethyl-6,13-dinitro-1,4,8,11-tetraazacyclotetradecan-1-ido)gold(III) and the orange acyclic complex (1,9-diamino-5-methyl-5-nitro-3,7-diazanoran-3-ido)gold(III) in good yields. Dissolution in strongly acidic solution gave the colourless fully protonated complexes. The pendant nitro groups are disposed on the same side of the macrocycle in a cis geometry, as confirmed by crystal structure analysis. In both complexes the gold ion lies in a square-planar environment of four nitrogen donors, and the co-ordinate bond to the deprotonated amine is shorter than the remaining Au-N distances.

Self-assembly of a tetranuclear macrocyclic copper(II) complex

A dinuclear macrocyclic complex is synthesized via the one-pot reaction of dipotassium nitroacetate, formaldehyde and a linear tetraamine copper(II) complex; the X-ray crystal structure of the product reveals an association of two dinuclear complexes to form a novel tetracopper(II) species.

H-1 NMR spectroscopic studies of the stability of an oxazolidine condensation product

Condensation of (-)-norephedrine with excess formaldehyde under mild conditions leads to formation of the 2:1 condensation product N,N'-methylenebis(4-methyl-5-phenyl)oxazolidine compared with the reaction with 1 mol of formaldehyde, which leads to 4-methyl-5-phenyloxazolidine. H-1 and C-13 NMR spectroscopy was used to monitor the stability of this compound and its decomposition products. The 2:1 condensation product is found to be stable in CDC1(3) but breaks down rapidly in CD3OD to yield a 50:50 mixture of 4-methyl-5-phenyloxazolidine and 3-hydroxymethyl-4-methyl-5-phenyloxazolidine. Upon addition of D2O to this equimolar mixture, the latter compound decomposes to norephedrine and formaldehyde, whereas the former compound is stable. (C) 1997 by John Wiley & Sons, Ltd.

Plasma Osteopontin Levels in Patients With Head and Neck Cancer Undergoing Chemoradiotherapy

Objectives: To explore the prognostic role of plasma levels of osteopontin (OPN), a phosphoglycoprotein with adhesive properties, in patients with head and neck squamous cell carcinoma (HNSCC) undergoing concomitant chemoradiotherapy. Previous studies have proposed OPN level as a prognostic factor in several cancers. Design: Prospective analysis of plasma OPN levels, before and within 12 weeks after treatment, in a cohort of patients with HNSCC undergoing platinum-based chemoradiotherapy at our center. Setting: Academic center. Patients: Sixty-nine patients diagnosed as having HNSCC. Interventions: Plasma levels of OPN were assessed before the start and after the conclusion of chemoradiotherapy by using an enzyme-linked immunosorbency assay kit. Chemoradiotherapy was exclusive (n = 52) or adjuvant to surgery (n = 17). Main Outcome Measures: Levels of OPN were correlated with clinicopathological characteristics, to treatment, and overall survival. Results: Pretreatment plasma OPN levels were higher in patients with advanced T and N stages compared with patients with early stages (P = .009 and .07, respectively). Mean (SD) plasma levels of OPN measured before (102.5 [68.1] ng/mL) and after (104.0 [53.6] ng/mL) treatment did not differ (P = .18, paired t test). Pretreatment and posttreatment levels of OPN were lower in patients who achieved a complete response compared with those who failed to respond (75.0 [41.5] vs 131.2 [82.9] ng/mL [P = .005] and 86.8 [40.5] vs 141.6 [58.4] ng/mL [P = .004], respectively). Patients with high pretreatment OPN levels (> 82.1 ng/mL) had shorter survival time (P < .001). Posttreatment OPN levels were marginally (P = .10) associated with survival time in univariate analysis. Conclusions: In patients with HNSCC undergoing chemoradiotherapy, a low pretreatment plasma OPN level is associated with treatment response and better survival. Modulation of OPN levels by chemoradiotherapy may also be associated with outcome. Further studies with serial measurement of OPN levels are warranted in these patients.

Bioactivation of Phenytoin by Human Cytochrome P450: Characterization of the Mechanism and Targets of Covalent Adduct Formation

The cytochrome P450-dependent covalent binding of radiolabel derived fi om phenytoin (DPH) and its phenol and catechol metabolites, 5-(4'-hydroxyphenyl)-5-phenylhydantoin (HPPH) and 5-(3',4'-dihydroxyphenyl)-5-phenylhydantoin (CAT), was examined in liver microsomes. Radiolabeled HPPH and CAT and unlabeled CAT were obtained from microsomal incubations and isolated by preparative HPLC. NADPH-dependent covalent binding was demonstrated in incubations of human liver microsomes with HPPH. When CAT was used as substrate, covalent adduct formation was independent of NADPH, was enhanced in the presence of systems generating reactive oxygen species, and was diminished under anaerobic conditions or in the presence of cytoprotective reducing agents. Fluorographic analysis showed that radiolabel derived from DPH and HPPH was selectively associated with proteins migrating with approximate relative molecular weights of 57-59 kDa and at the dye front (molecular weights < 23 kDa) on denaturing gels. Lower levels of radiolabel were distributed throughout the molecular weight range. In contrast, little selectivity was seen in covalent adducts formed from CAT. HPPH was shown to be a mechanism-based inactivator of P450, supporting the contention that a cytochrome P450 is one target of covalent binding. These results suggest that covalent binding of radiolabel derived from DPH in rat and human Liver microsomes occurs via initial P450-dependent catechol formation followed by spontaneous oxidation to quinone and semiquinone derivatives that ultimately react with microsomal protein. Targets for covalent binding may include P450s, though the catechol appears to be sufficiently stable to migrate out of the P450 active site to form adducts with other proteins. In conclusion, we have demonstrated that DPH can be bioactivated in human liver to metabolites capable of covalently binding to proteins. The relationship of adduct formation to DPH-induced hypersensitivity reactions remains to be clarified.

The chemistry of novolac resins .3. C-13 and N-15 nmr studies of curing with hexamethylenetetramine

The reactions between novolac resins and hexamethylenetetramine (HMTA) which occur on curing have been studied by C-13 and N-15 high-resolution n.m.r. in both solution and the solid state. Strong evidence for the existence of many curing intermediates is obtained. New curing intermediates are reported along with experimental data to support previously postulated intermediates. The initial curing reactions between novolac and HMTA produce various substituted benzoxazines and benzylamines. Thermal decomposition/oxidation and further reactions of these initial intermediates generate methylene linkages between phenolic rings for chain extension and cross-linking. Among the three kinds of methylene linkages, the para-para methylene linkages are formed at relatively lower temperatures. Various imine, amide and imide side-products also concurrently appear during the process. The initial amount of HMTA plays a critical role in the curing reactivity and chemical structures of the cured resins. The lower the amount of HMTA, the lower the temperature at which curing occurs, and the lower the amount of the nitrogen-containing side-products in the finally cured resins. The ortho-linked intermediates are relatively stable, and can remain in the cured resins up to higher temperatures. The study provides an extensive description of the curing reactions of novolac resins. (C) 1997 Elsevier Science Ltd.

Partial lesions of the intratemporal segment of the facial nerve: Graft versus partial reconstruction

Objectives: In cases of partial lesions of the intratemporal segment of the facial nerve, should the surgeon perform an intraoperative partial reconstruction, or partially remove the injured segment and place a graft? We present results from partial lesion reconstruction on the intratemporal segment of the facial nerve. Methods: A retrospective study on 42 patients who presented partial lesions on the intratemporal segment of the facial nerve was performed between 1988 and 2005. The patients were divided into 3 groups based on the procedure used: interposition of the partial graft on the injured area of the nerve (group 1; 12 patients); keeping the preserved part and performing tubulization (group 2; 8 patients); and dividing the parts of the injured nerve (proximal and distal) and placing a total graft of the sural nerve (group 3; 22 patients). Results: Fracture of the temporal bone was the most frequent cause of the lesion in all groups, followed by iatrogenic causes (p < 0.005). Those who obtained results lower than or equal to III on the House-Brackmann scale were 1 (8.3%) of the patients in group 1, none (0.0%) of the patients in group 2, and 15 (68.2%) of the patients in group 3 (p < 0.001). Conclusions: The best surgical technique for therapy of a partial lesion of the facial nerve is still questionable. Among these 42 patients, the best results were those from the total graft of the facial nerve.

Application of fibrin glue in microvascular anastomoses: Comparative analysis with the conventional suture technique using a free flap model

Background: Several studies have already reported the utilization of fibrin glue in microvascular anastomoses to minimize the number of sutures and to decrease the operative time. Despite the good results obtained in most of these experiments, its clinical application has not launched. The aim of this study was to clarify the controversies around the safeness of fibrin glue application in microvascular anastomoses, and also to demonstrate the potential benefits of fibrin glue application in a realistic free flap model. Methods: Twenty-seven rabbits were used in this study The experimental model consisted of a free groin flap transfer to the anterior cervical region. The flap`s circulation was restored by means of an end-to-side anastomosis between the femoral and carotid arteries, and an end-to-end anastomosis between the femoral and external jugular veins. The animals were divided into two groups (n = 10) according to the anastomosis technique: Group I (conventional suture) and group 11 (fibrin glue). Results: The number of sutures required to complete the arterial and venous anastomoses was reduced in 39 and 37% in group 11, respectively. Despite this reduction, the anastomoses maintained adequate patency rates and mechanical strength. Both arterial and venous anastomoses benefited from fibrin glue application, which made them easier and faster to perform. The flaps` ischemic time and the total operative time were also significantly shortened. Conclusions: In this study, the application of fibrin glue in microvascular anastomoses was safe and reliable. The risk-benefit ratio of fibrin glue application in microvascular anastomoses is favorable for its use. (c) 2008 Wiley-Liss, Inc.

Leishmania sp identification by PCR associated with sequencing of target SSU rDNA in paraffin-embedded skin samples stored for more than 30 years

Paraffin-embedded samples commonly stored at educational and research institutions constitute tissues banks for follow-up or epidemiological studies; however, the paraffin inclusion process involves the use of substances that can cause DNA degradation. In this study, a PCR protocol was applied to identify Leishmania strains in 33 paraffin-embedded skin samples of patients with American cutaneous leishmaniasis. DNA was obtained by the phenol-chloroform protocol following paraffin removal and then used in PCR or nested PCR based on the nucleotide sequence of the small subunit ribosomal RNA (SSU rDNA). The amplicons obtained were cloned and sequenced to determine the single nucleotide polymorphism that distinguishes between different Leishmania species or groups. This assay allowed to distinguish organisms belonging to the subgenus Viannia and identify L. (Leishmania) amazonensis and L. (L.) chagasi of the Leishmania subgenus. Of the 33 samples, PCR and nested PCR identified 91% of samples. After sequencing the PCR product of 26 samples, 16 were identified as L. (L.) amazonensis, the other 10 contain organisms belonging to the L. (Viannia) sub-genus. These results open a huge opportunity to study stored samples and promote relevant contributions to epidemiological studies.

Histological evaluation of biocompatibility of lyophilized bovine pericardium implanted subcutaneously in rats

This article aims at investigating in vivo evaluation of lyophilization procedure on the biocompatibility of bovine pericardium treated with glutaraldehyde (GA). The bovine pericardium was fixed with 0.5% glutaraldehyde during 10 days and preserved in 4% formaldehyde (FA). Two groups of samples were prepared from treated membranes: Group 1, nonlyophilized samples and Group 2, lyophilized samples. Male Sprague-Dawley rats (4 weeks after birth) were anesthetized (pentobarbital sodium 25 mg/kg of body weight) and in each one were implanted subcutaneously in the dorsal region a sample from Group 1 and another from Group 2. These samples were explanted after 30 days for histological analysis. No intercurrences took place after the surgery. No differences (P > 0.05) in the calcification, granulomatous reaction, mononuclear infiltration, and granulation tissue development was observed between both groups. The implanted lyophilized samples presented a trend for a reduced inflammatory reaction. Lyophilization of the bovine pericardium does not seem to increase the above listed tissue reaction.

Molecular biology in tropical dermatoses

Initially, basic concepts are presented concerning the cell, genetic code and protein synthesis, and some techniques of molecular biology, such as PCR, PCR-RFLP, DNA sequencing, RT-PCR and immunoblotting. Protocols of nucleotides and of proteins extraction are supplied, such as salting out in peripheral blood allied to phenol-chloroform and trizol methods in skin samples. To proceed, commented examples of application of those techniques of molecular biology for the etiologic diagnosis and for research in tropical dermatoses, with emphasis to American tegumentary leishmaniasis and leprosy are presented.

Increased Capsaicin Receptor TRPV1 in the Peritoneum of Women With Chronic Pelvic Pain

Objective: To investigate the expression of capsaicin receptor [transient receptor potential vanilloid type-1 (TRPV1)] in the peritoneum of women with chronic pelvic pain (CPP). Methods: A case-control study was conducted on 25 women with CPP and 10 controls. Samples of the rectouterine excavation (2 cm 2) were obtained by laparoscopy, fixed in 4% formaldehyde, and underwent immunohistochemistry analysis using rabbit anti-TRPV1 (1:400) polyclonal antibodies and anti-protein gene product 9.5 (PGP 9.5) (1:2000) as a neuronal marker. Ten sequential images of high magnification fields ( x 40) were captured from each slide and the area identified with the antibody was calculated with Kontron V2.0 software. Results: Immunoreactivity to TRPV1 was sparsely detected in the nervous tissue and epithelium of endometriotic lesions. The percent area of immunoreactivity for TRPV1 [expressed as median (range)] was greater in specimens from women with CPP, 1.02% (0.54 to 2.93), than from women without the disease, 0.14% (0.07 to 1.12) (P<0.0001). This greater expression was not secondary to an increase in neuronal fibers because there was also a significant difference in the percent area TRPV1:PGP 9.5 ratio between women with CPP, 1.18 (0.26 to 4.63), and controls, 0.15 (0.06 to 0.95) (P = 0.0003). Discussion: TRPV1 may play an important role in the maintenance and perpetuation of symptoms in women with CPP. In view of the immunoreactivity detected for TRPV1, the endometriotic lesion may have the ability to interfere with nociception or with the inflammatory peritoneal environment in women with CPP. Further Studies are needed to elucidate the participation of TRPV1 in CPP and its association with endometriosis.

Low-dose transdermal hormone therapy does not interfere with the blood pressure of hypertensive menopausal women: a pilot study

Objectives To determine the effects of low-dose transdermal hormone therapy (HT) on systolic (SBP) and diastolic (DBP) blood pressure (BP) evaluated by 24-h ambulatory blood pressure monitoring (ABPM) in hypertensive postmenopausal women. Methods The study was conducted on 24 hypertensive postmenopausal women aged, on average, 54 years and under treatment with enalapril maleate (10-20 mg/day) combined or not with hydrochlorothiazide (25 mg/day). Thirteen women used a transdermal adhesive containing estradiol and norethisterone (25 and 125 mu g active substance/day, respectively) and 11 did not receive HT. ABPM, lipid profile, and climacteric symptoms were evaluated before and 3 and 6 months after treatment. Results After 3 and 6 months of follow-up, there was a statistically significant reduction of the Blatt-Kupperman menopausal index in the treated group (19.6 +/- 8.3 vs. 9.6 +/- 5.9 vs. 9.7 +/- 7.0; P=0.01). No significant difference in any of the ABPM variables (areas under the systolic and diastolic curves, mean SBP and DBP, SBP and DBP loads and wakefulness-sleep variation) or in the lipid profile was observed between or within groups at the three time points studied. Conclusion Low-dose transdermal HT administered for 6 months was effective in improving climacteric symptoms and did not change BP values or circadian pattern in postmenopausal women with mild-to-moderate arterial hypertension taking antihypertensive medications.

TRPV1 Expression on Peritoneal Endometriosis Foci is Associated With Chronic Pelvic Pain

Objective: To investigate the expression of capsaicin receptor (transient receptor potential vanilloid type 1 [TRPV1]) in the peritoneal endometriosis foci of women with and without chronic pelvic pain (CPP). Methods: A case-control study was conducted on 49 women with endometriosis who underwent laparoscopy, 28 of whom had CPP and 21 without CPP. Samples from peritoneum of the rectouterine excavation (2 cm(2)) were obtained by laparoscopy, fixed in 4% formaldehyde, and underwent immunohistochemistry analysis using rabbit anti-TRPV1 (1:400) polyclonal antibody. Results: Image analysis revealed that the immunoreactivity for TRPV1 was more frequent in specimens (endometriosis foci) from women with CPP (n = 15 of 28, 53.6%), compared to samples from the endometriosis foci of women without CPP (n = 6 of 21, 28.6%; P = .04). There was no correlation with duration, intensity of pain, or stage of the disease (endometriosis). Discussion: The present study shows that TRPV1 expression in peritoneal endometriosis foci is related to CPP in women. However, this association is not related to the endometriosis stage. In view of the immunoreactivity for TRPV1 observed here, we believe that some endometriotic lesions may provide a scenario for TRPV1 to be tonically active and this activity may contribute to the underlying pathology of CPP.