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1.
Langenbecks Arch Surg ; 407(6): 2273-2279, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35551467

ABSTRACT

BACKGROUND: The standard treatment for pT3N0 gastric cancer (GC) in Japanese guidelines is radical surgery without adjuvant chemotherapy. However, certain percentages of these patients develop recurrences; therefore, detecting the high-risk subgroup of recurrence may contribute to improve patient's outcome by adjuvant chemotherapy. In this study, we aimed to identify a predictive indicator of poor prognosis in pT3N0 GC. METHODS: Eighty-one patients who were diagnosed as pT3N0 GC after curative surgical resection and had not received adjuvant chemotherapy were included. The clinicopathological factors and laboratory parameters were evaluated by univariate and multivariate analyses to identify prognostic factors of tumor recurrence. Survival analysis was performed by Kaplan-Meier method. RESULTS: Male (P = 0.027), a high body mass index (BMI) (P = 0.031), a high CA19-9 value (P = 0.025), and a lower number of retrieved lymph nodes (P = 0.018) were found to be significantly associated with a shorter recurrence free survival (RFS). In a multivariate analysis, high CA19-9 value (> 37 U/ml) [(hazard ratio (HR): 3.326; 95% confidence interval (CI): 1.044 to 10.596; P = 0.042] was found to be an independent predictor of RFS. CONCLUSION: The preoperative high CA19-9 value is considered a useful prognostic marker for predicting cancer recurrence after curative surgery in pT3N0 GC patients. For those patients, adjuvant chemotherapy might be considered to improve the survival outcome.


Subject(s)
CA-19-9 Antigen , Stomach Neoplasms , Chemotherapy, Adjuvant/methods , Humans , Male , Neoplasm Recurrence, Local/surgery , Prognosis , Retrospective Studies , Stomach Neoplasms/pathology
2.
Appl Opt ; 59(3): 742-747, 2020 Jan 20.
Article in English | MEDLINE | ID: mdl-32225203

ABSTRACT

We fabricated a binary diffractive lens to control focal distribution, such as intensity distribution, by controlling the focal length and depth of focus. The results revealed changes in the focal length and depth of focus as a function of changes in the ring zone interval ΔRM at the end of the lens. Similar results were obtained from experiments. The peak position on the optical axis shifts further away from the lens. The half-width in the propagation direction increases with the ΔRM. These results demonstrate the possibility of controlling the focal distribution using single flat lenses by changing the periodic structure.

3.
Gan To Kagaku Ryoho ; 43(12): 1875-1877, 2016 Nov.
Article in Japanese | MEDLINE | ID: mdl-28133161

ABSTRACT

A 69-year-old man underwent esophagogastroduodenoscopy, which showed a slightly depressed lesion at the greater curvature of the gastric body. We diagnosed gastric adenocarcinoma of the fundic gland type(GA-FG)from examination of the biopsy specimen. Endoscopic submucosal dissection(ESD)was performed for curative resection. The pathological examination revealed a positive vertical margin. Consequently, laparoscopic gastrectomy was additionally performed. GA-FG has recently been proposed as a new entity of gastric adenocarcinoma. GA-FG mostly develops without Helicobacter pylori infection and often invades the submucosa, regardless of size. However, GA-FG rarely demonstrates lymphatic and venous invasion despite deep submucosal invasion. Since most GA-FG cases undergo ESD, few reports of surgical resection exist. Here, we report our experience of laparoscopic gastrectomy for GA-FG.


Subject(s)
Adenocarcinoma/surgery , Stomach Neoplasms/surgery , Aged , Biopsy , Gastrectomy , Humans , Laparoscopy , Male , Stomach Neoplasms/pathology , Treatment Outcome
4.
ACS Nano ; 9(3): 3206-14, 2015 Mar 24.
Article in English | MEDLINE | ID: mdl-25738973

ABSTRACT

Manipulation of individual graphene sheets/films into specific architectures at macroscopic scales is crucially important for practical uses of graphene. We present herein a versatile and robust method based on annealing of solid carbon precursors on nickel templates and thermo-assisted removal of poly(methyl methacrylate) under low vacuum of ∼0.6 Pa for fabrication of macroscopic, freestanding, and tubular graphene (TG) architectures. Specifically, the TG architectures can be obtained as individual and woven tubes with a diameter of ∼50 µm, a wall thickness in the range of 2.1-2.9 nm, a density of ∼1.53 mg·cm(-3), a thermal stability up to 600 °C in air, an electrical conductivity of ∼1.48 × 10(6) S·m(-1), and field emission current densities on the order of 10(4) A·cm(-2) at low applied electrical fields of 0.6-0.7 V·µm(-1). These properties show great promise for applications in flexible and lightweight electronics, electron guns, or X-ray tube sources.

5.
Atherosclerosis ; 229(1): 182-5, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23639859

ABSTRACT

Evaluation of atherosclerotic plaques depends on invasive intravascular ultrasonography (IVUS). Carboxy-terminal telopeptide of type I collagen (ICTP) is produced by matrix metalloproteinase (MMP)-dependent digestion of type I collagen. Because vulnerable plaques are rich in type I collagen and MMPs from macrophages, we examined the association between serum ICTP and coronary plaques in patients with coronary disease. We recruited 46 men and 17 women without renal failure or bone diseases affecting serum ICTP, who underwent coronary IVUS. Serum ICTP levels were higher in patients with coronary plaques containing more than 10% necrotic core area than in patients with less than 10% necrotic core area. A positive correlation was found between serum ICTP and necrotic core area. Only serum ICTP was positively correlated with necrotic core area by multivariate analysis (p < 0.05). These results suggest that serum ICTP can be used as a non-invasive marker of vulnerable plaques in atherosclerotic patients.


Subject(s)
Collagen Type I/blood , Coronary Artery Disease/blood , Coronary Artery Disease/epidemiology , Peptides/blood , Plaque, Atherosclerotic/blood , Plaque, Atherosclerotic/epidemiology , Acute Coronary Syndrome/blood , Acute Coronary Syndrome/epidemiology , Acute Coronary Syndrome/pathology , Aged , Aged, 80 and over , Biomarkers/blood , Coronary Artery Disease/pathology , Cross-Sectional Studies , Female , Humans , Male , Matrix Metalloproteinases/metabolism , Middle Aged , Morbidity , Necrosis , Pilot Projects , Plaque, Atherosclerotic/pathology , Risk Factors
6.
Hinyokika Kiyo ; 58(8): 395-9, 2012 Aug.
Article in Japanese | MEDLINE | ID: mdl-23052261

ABSTRACT

To determine the follow-up schedule in patients with non-muscle-invasive bladder cancer who had remained recurrence-free for 5 or more years, we retrospectively reviewed 258 patients with Ta and T1 bladder cancer who had been free of recurrence for at least 5 years. Of these 258 patients, subsequent recurrences developed in 100 patients. In spite of our recommendation that cystoscopic follow-up be done at 12-month intervals for patients who remained recurrence-free for more than 5 years, 45 had been followed at intervals of more than 12 months (range, 13-77 months) when the recurrences were found. Of 100 recurrent tumors, 20 (20.0%) showed bladder muscle invasion. Muscle-invasive cancer was identified more often in the patients with cytoscopic intervals of more than 12 months than in those of less than 12 months (35.6% versus 7.3%). Therefore, we recommend that cystoscopy be performed at intervals of less than 12 months in patients with non-muscle invasive bladder cancer for recurrence detection before tumors become muscle invasive, even when patients remain free of recurrence for a long period.


Subject(s)
Urinary Bladder Neoplasms/mortality , Cystoscopy , Disease-Free Survival , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Time Factors , Urinary Bladder Neoplasms/pathology
7.
J Am Chem Soc ; 134(15): 6584-95, 2012 Apr 18.
Article in English | MEDLINE | ID: mdl-22468558

ABSTRACT

The negative ion chemistry of five azine molecules has been investigated using the combined experimental techniques of negative ion photoelectron spectroscopy to obtain electron affinities (EA) and tandem flowing afterglow-selected ion tube (FA-SIFT) mass spectrometry to obtain deprotonation enthalpies (Δ(acid)H(298)). The measured Δ(acid)H(298) for the most acidic site of each azine species is combined with the EA of the corresponding radical in a thermochemical cycle to determine the corresponding C-H bond dissociation energy (BDE). The site-specific C-H BDE values of pyridine, 1,2-diazine, 1,3-diazine, 1,4-diazine, and 1,3,5-triazine are 110.4 ± 2.0, 111.3 ± 0.7, 113.4 ± 0.7, 107.5 ± 0.4, and 107.8 ± 0.7 kcal mol(-1), respectively. The application of complementary experimental methods, along with quantum chemical calculations, to a series of nitrogen-substituted azines sheds light on the influence of nitrogen atom substitution on the strength of C-H bonds in six-membered rings.

8.
J Am Soc Mass Spectrom ; 22(7): 1260-72, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21953109

ABSTRACT

The gas phase reactivity of 1,3,5-triazine with several oxyanions and carbanions, as well as amide, was evaluated using a flowing afterglow-selected ion flow tube mass spectrometer. Isotopic labeling, H/D exchange, and collision induced dissociation experiments were conducted to facilitate the interpretation of structures and fragmentation processes. A multi-step (→ HCN + HC(2)N (2) (-) → CN(-) + 2 HCN) and/or single-step (→ CN(-) + 2 HCN) ring-opening collision-induced fragmentation process appears to exist for 1,3,5-triazinide. In addition to proton and hydride transfer reactions, the data indicate a competitive nucleophilic aromatic addition pathway (S(N)Ar) over a wide range of relative gas phase acidities to form strong anionic σ-adducts (Meisenheimer complexes). The significant hydride acceptor properties and stability of the anionic σ-adducts are rationalized by extremely electrophilic carbon centers and symmetric charge delocalization at the electron-withdrawing nitrogen positions. The types of anion-arene binding motifs and their influence on reaction pathways are discussed.


Subject(s)
Anions/chemistry , Gases/chemistry , Hydrogen/chemistry , Mass Spectrometry/methods , Triazines/chemistry , Deuterium Exchange Measurement , Protons
9.
Hinyokika Kiyo ; 56(9): 535-8, 2010 Sep.
Article in Japanese | MEDLINE | ID: mdl-20940532

ABSTRACT

Leiomyosarcoma is a malignant soft-tissue cancer arising from tissues containing smooth muscle. It commonly occurs in the gastrointestinal system and retroperitoneum, but is rare in the genito-urinary system. We experienced a case of primary testicular leiomyosarcoma. A 71-year-old man presented with painless swelling of the right scrotal contents for 4 months. A high orchiectomy was performed. Histological examination revealed primary testicular leiomyosarcoma. The patient did not receive any adjuvant therapy. Seven months after the operation, there has been no recurrence. Cases of primary intratesticular leiomyosarcoma are rare. To the best of our knowledge, only sixteen cases have been reported in the literature.


Subject(s)
Leiomyosarcoma/pathology , Testicular Neoplasms/pathology , Aged , Humans , Male
10.
Hinyokika Kiyo ; 54(8): 573-5, 2008 Aug.
Article in Japanese | MEDLINE | ID: mdl-18788451

ABSTRACT

We present a case of isolated adrenocorticotrophic hormone (ACTH) deficiency (IAD) in a late onset hypogonadism (LOH) clinic, not diagnosed by examinations in internal medicine. A 54-year-old man showed body weight loss with severe appetite loss, general malaise and hypotension. He visited our clinic for a checkup for LOH after general examinations in internal medicine. His hormonal examination showed undetectable ACTH and cortisol levels. However, the values of other pituitary hormones and testosterone were normal. A load test for anterior pituitary hormone (CRH + TRH + LHRH + GRH test) revealed that the ACTH-cortisol system showed no response although the other pituitary hormones responded. These findings confirmed the diagnosis of isolated ACTH deficiency. Administration of hydrocortisone dramatically improved his symptoms. Symptoms of IAD are similar to those of LOH syndrome and depression. Thus, we should consider IAD as one of the differential diagnoses in LOH clinics.


Subject(s)
Adrenocorticotropic Hormone/deficiency , Hypogonadism/diagnosis , Hypogonadism/etiology , Andropause , Diagnosis, Differential , Humans , Hydrocortisone/administration & dosage , Hydrocortisone/deficiency , Hypogonadism/drug therapy , Male , Middle Aged , Treatment Outcome
11.
J Phys Chem A ; 112(40): 9723-30, 2008 Oct 09.
Article in English | MEDLINE | ID: mdl-18774783

ABSTRACT

The 363.8 nm photoelectron spectrum of the iminodiazomethyl anion has been measured. The anion is synthesized through the reaction of the hydroxide ion (HO-) with 1 H-1,2,3-triazole in helium buffer gas in a flowing afterglow ion source. The observed spectrum exhibits well-resolved vibronic structure of the iminodiazomethyl radical. Electronic structure calculations have been performed at the B3LYP/6-311++G(d,p) level of theory to study the molecular structure of the ion. Equilibrium geometries of four possible conformers of the iminodiazomethyl anion have been obtained from the calculations. Spectral simulations have been performed on the basis of the calculated geometries and normal modes of these conformationally isomeric ions and the corresponding radicals. The spectral analysis suggests that the ions of two conformations are primarily formed in the aforementioned reaction. The relative abundance of the two conformers substantially deviates from the thermal equilibrium populations, and it reflects the potential energy surfaces relevant to conformational isomerization processes. The electron affinities of the ( ZE)- and ( EE)-iminodiazomethyl radicals have been determined to be 2.484 +/- 0.007 and 2.460 +/- 0.007 eV, respectively. The energetics of the iminodiazomethyl anion is compared with that of the most stable structural isomer, the 1,2,3-triazolide ion. Collision-induced dissociation of the 1,2,3-triazolide ion has also been studied in flowing afterglow-selected ion flow tube experiments. Facile fragmentation generating a product ion of m/ z 40 has been observed. DFT calculations suggest that fragmentation of the 1,2,3-triazolide ion to the cyanomethyl anion and N2 is exothermic. The stability of the ion is discussed in comparison with other azolide ions with different numbers of N atoms in the five-membered ring.

12.
J Phys Chem A ; 112(39): 9516-25, 2008 Oct 02.
Article in English | MEDLINE | ID: mdl-18570357

ABSTRACT

The E(CO)2 elimination reactions of alkyl hydroperoxides proceed via abstraction of an alpha-hydrogen by a base: X(-) + R(1)R(2)HCOOH --> HX + R(1)R(2)C=O + HO(-). Efficiencies and product distributions for the reactions of the hydroxide anion with methyl, ethyl, and tert-butyl hydroperoxides are studied in the gas phase. On the basis of experiments using three isotopic analogues, HO(-) + CH3OOH, HO(-) + CD3OOH, and H(18)O(-) + CH3OOH, the overall intrinsic reaction efficiency is determined to be 80% or greater. The E(CO)2 decomposition is facile for these methylperoxide reactions, and predominates over competing proton transfer at the hydroperoxide moiety. The CH3CH2OOH reaction displays a similar E(CO)2 reactivity, whereas proton transfer and the formation of HOO(-) are the exclusive pathways observed for (CH3)3COOH, which has no alpha-hydrogen. All results are consistent with the E(CO)2 mechanism, transition state structure, and reaction energy diagrams calculated using the hybrid density functional B3LYP approach. Isotope labeling for HO(-) + CH3OOH also reveals some interaction between H2O and HO(-) within the E(CO)2 product complex [H2O...CH2=O...HO(-)]. There is little evidence, however, for the formation of the most exothermic products H2O + CH2(OH)O(-), which would arise from nucleophilic condensation of CH2=O and HO(-). The results suggest that the product dynamics are not totally statistical but are rather direct after the E(CO)2 transition state. The larger HO(-) + CH3CH2OOH system displays more statistical behavior during complex dissociation.

13.
Urology ; 71(4): 586-91; discussion 591-2, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18387387

ABSTRACT

OBJECTIVES: To clarify the influences of shock wave lithotripsy (SWL) treatments for renal and ureteropelvic junction stones on new onsets of hypertension and diabetes mellitus (DM). METHODS: We compared the new onsets of hypertension and DM after SWL in renal and ureteral stone groups. The renal stone group consisted of 772 patients treated with SWL, who had a possibility of renal and pancreatic shock wave damage. The ureteral stone group consisted of 505 patients treated with SWL, who were unlikely to have suffered SWL damage in the kidney and pancreas areas. Both treatment groups received SWL between 1984 and 1994. RESULTS: The rates of new onset of hypertension in the renal stone and ureteral stone groups were 22.8% and 20.0% in men and 23.1% and 20.5% in women, respectively. The rates of new onset of DM in the renal stone and ureteral stone groups were 7.4% and 11.0% in men and 8.7% and 8.7% in women, respectively. There was no significant difference in the new onsets of hypertension and DM between renal and ureteral stone groups depending on each age decade or sex. Treatment for renal stone was not a significant risk factor for new onsets of hypertension and DM by logistic regression analysis. CONCLUSIONS: Our findings suggest that SWL treatment for renal and UPJ stones might not be associated with new onset of hypertension or DM.


Subject(s)
Diabetes Mellitus/epidemiology , Hypertension/epidemiology , Kidney Calculi/therapy , Lithotripsy/adverse effects , Ureteral Calculi/therapy , Adult , Age Distribution , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Kidney Calculi/complications , Male , Middle Aged , Odds Ratio , Retrospective Studies , Risk Factors , Sex Distribution , Ureteral Calculi/complications
14.
J Phys Chem B ; 112(2): 545-57, 2008 Jan 17.
Article in English | MEDLINE | ID: mdl-17960930

ABSTRACT

A combination of experimental methods, photoelectron-imaging spectroscopy, flowing afterglow-photoelectron spectroscopy and the flowing afterglow-selected ion flow tube technique, and electronic structure calculations at the B3LYP/6-311++G(d,p) level of density functional theory (DFT) have been employed to study the mechanism of the reaction of the hydroxide ion (HO-) with 1H-1,2,3-triazole. Four different product ion species have been identified experimentally, and the DFT calculations suggest that deprotonation by HO- at all sites of the triazole takes place to yield these products. Deprotonation of 1H-1,2,3-triazole at the N1-H site gives the major product ion, the 1,2,3-triazolide ion. The 335 nm photoelectron-imaging spectrum of the ion has been measured. The electron affinity (EA) of the 1,2,3-triazolyl radical has been determined to be 3.447 +/- 0.004 eV. This EA and the gas-phase acidity of 2H-1,2,3-triazole are combined in a negative ion thermochemical cycle to determine the N-H bond dissociation energy of 2H-1,2,3-triazole to be 112.2 +/- 0.6 kcal mol-1. The 363.8 nm photoelectron spectroscopic measurements have identified the other three product ions. Deprotonation of 1H-1,2,3-triazole at the C5 position initiates fragmentation of the ring structure to yield a minor product, the ketenimine anion. Another minor product, the iminodiazomethyl anion, is generated by deprotonation of 1H-1,2,3-triazole at the C4 position, followed by N1-N2 bond fission. Formation of the other minor product, the 2H-1,2,3-triazol-4-ide ion, can be rationalized by initial deprotonation of 1H-1,2,3-triazole at the N1-H site and subsequent proton exchanges within the ion-molecule complex. The EA of the 2H-1,2,3-triazol-4-yl radical is 1.865 +/- 0.004 eV.

15.
J Phys Chem A ; 111(34): 8374-83, 2007 Aug 30.
Article in English | MEDLINE | ID: mdl-17676828

ABSTRACT

The 351.1 nm photoelectron spectrum of the vinyldiazomethyl anion has been measured. The ion is generated through the reaction of the allyl anion with N(2)O in helium buffer gas in a flowing afterglow source. The spectrum exhibits the vibronic structure of the vinyldiazomethyl radical in its electronic ground state as well as in the first excited state. Electronic structure calculations have been performed for these molecules at the B3LYP/6-311++G(d,p) level of theory. A Franck-Condon simulation of the X (2)A'' state portion of the spectrum has been carried out using the geometries and normal modes of the anion and radical obtained from these calculations. The simulation unambiguously shows that the ions predominantly have an E conformation. The electron affinity (EA) of the radical has been determined to be 1.864 +/- 0.007 eV. Vibrational frequencies of 185 +/- 10 and 415 +/- 20 cm(-1) observed in the spectrum have been identified as in-plane CCN bending and CCC bending modes, respectively, for the X (2)A'' state. The spectrum for the A (2)A' state is broad and structureless, reflecting large geometry differences between the anion and the radical, particularly in the CCN angle, as well as vibronic coupling with the X (2)A'' state. The DFT calculations have also been used to better understand the mechanism of the allyl anion reaction with N(2)O. Collision-induced dissociation of the structural isomer of the vinyldiazomethyl anion, the 1-pyrazolide ion, has been examined, and energetics of the structural isomers is discussed.

16.
J Phys Chem A ; 111(35): 8579-87, 2007 Sep 06.
Article in English | MEDLINE | ID: mdl-17696508

ABSTRACT

The 351.1 nm photoelectron spectra of the N-methyl-5-pyrazolide anion and the N-methyl-5-imidazolide anion are reported. The photoelectron spectra of both isomers display extended vibrational progressions in the X2A' ground states of the corresponding radicals that are well reproduced by Franck-Condon simulations, based on the results of B3LYP/6-311++G(d,p) calculations. The electron affinities of the N-methyl-5-pyrazolyl radical and the N-methyl-5-imidazolyl radical are 2.054 +/- 0.006 eV and 1.987 +/- 0.008 eV, respectively. Broad vibronic features of the A(2)A' ' states are also observed in the spectra. The gas-phase acidities of N-methylpyrazole and N-methylimidazole are determined from measurements of proton-transfer rate constants using a flowing afterglow-selected ion flow tube instrument. The acidity of N-methylpyrazole is measured to be Delta(acid)G(298) = 376.9 +/- 0.7 kcal mol(-1) and Delta(acid)H(298) = 384.0 +/- 0.7 kcal mol(-1), whereas the acidity of N-methylimidazole is determined to be Delta(acid)G(298) = 380.2 +/- 1.0 kcal mol(-1) and Delta(acid)H(298)= 388.1 +/- 1.0 kcal mol(-1). The gas-phase acidities are combined with the electron affinities in a negative ion thermochemical cycle to determine the C5-H bond dissociation energies, D(0)(C5-H, N-methylpyrazole) = 116.4 +/- 0.7 kcal mol(-1) and D(0)(C5-H, N-methylimidazole) = 119.0 +/- 1.0 kcal mol(-1). The bond strengths reported here are consistent with previously reported bond strengths of pyrazole and imidazole; however, the error bars are significantly reduced.

17.
J Am Chem Soc ; 129(32): 9976-85, 2007 Aug 15.
Article in English | MEDLINE | ID: mdl-17658801

ABSTRACT

A direct dynamics simulation at the B3LYP/6-311+G(d,p) level of theory was used to study the F- + CH3OOH reaction dynamics. The simulations are in excellent agreement with a previous experimental study (J. Am. Chem. Soc. 2002, 124, 3196). Two product channels, HF + CH2O + OH- and HF + CH3OO-, are observed. The former dominates and occurs via an ECO2 mechanism in which F- attacks the CH3- group, abstracting a proton. Concertedly, a carbon-oxygen double bond is formed and OH- is eliminated. Somewhat surprisingly this is not the reaction path, predicted by the intrinsic reaction coordinate (IRC), which leads to a deep potential energy minimum for the CH2(OH)2...F- complex followed by dissociation to HF + CH2(OH)O-. None of the direct dynamics trajectories followed this path, which has an energy release of -63 kcal/mol and is considerably more exothermic than the ECO2 path whose energy release is -27 kcal/mol. Other product channels not observed, and which have a lower energy than that for the ECO2 path, are F- + CO + H2 + H2O (-43 kcal/mol), F- + CH2O + H2O (-51 kcal/mol), and F- + CH2(OH)2 (-60 kcal/mol). Formation of the CH3OOH...F- complex, with randomization of its internal energy, is important, and this complex dissociates via the ECO2 mechanism. Trajectories which form HF + CH3OO- are nonstatistical events and, for the 4 ps direct dynamics simulation, are not mediated by the CH3OOH...F- complex. Dissociation of this complex to form HF + CH3OO- may occur on longer time scales.

19.
Int J Urol ; 14(4): 339-42; discussion 343, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17470167

ABSTRACT

OBJECTIVES: To study the dropout rate for use of sildenafil after initial prescription and during successful treatment to clarify their risk factors. METHODS: A total of 1036 patients with erectile dysfunction who were treated with sildenafil were analyzed. The dropout rate during successful treatment and its risk factors were assessed using the Kaplan-Meier method and Cox proportional hazards model, respectively. RESULTS: Thirty-one percent (n = 322) of the patients dropped out after the initial prescription. The cumulative dropout rate during successful treatment at 3 years after starting usage was 48%. A lower International Index of Erectile Function (IIEF-5) score before treatment was a significant risk factor for dropout during a successful treatment course (P < 0.029 by the Cox proportional hazards model). CONCLUSIONS: Approximately 30% and 50% of the patients dropped out of treatment after the first prescription and at 3-year follow-up, respectively. Adequate initial instruction and long-term follow-up are required even for patients with successful treatment.


Subject(s)
Erectile Dysfunction/drug therapy , Patient Dropouts/statistics & numerical data , Phosphodiesterase Inhibitors/administration & dosage , Piperazines/administration & dosage , Sulfones/administration & dosage , Treatment Refusal/statistics & numerical data , Adult , Aged , Drug Administration Schedule , Follow-Up Studies , Humans , Male , Middle Aged , Purines/administration & dosage , Risk Factors , Sildenafil Citrate , Treatment Outcome
20.
J Am Soc Mass Spectrom ; 18(6): 1046-51, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17448673

ABSTRACT

This work describes the first experimental studies of deuterium kinetic isotope effects (KIEs) for the gas-phase E2 reactions of microsolvated systems. The reactions of F(-)(H(2)O)(n) and OH(-)(H(2)O)(n), where n = 0, 1, with (CH(3))(3)CX (X = Cl, Br), as well as the deuterated analogs of the ionic and neutral reactants, were studied utilizing the flowing afterglow-selected ion flow tube technique. The E2 reactivity is found to decrease with solvation. Small, normal kinetic isotope effects are observed for the deuteration of the alkyl halide, while moderately inverse kinetic isotope effects are observed for the deuteration of the solvent. Minimal clustering of the product ions is observed, but there are intriguing differences in the nature and extent of the clustering process. Electronic structure calculations of the transition states provide qualitative insight into these microsolvated E2 reactions.


Subject(s)
Deuterium/chemistry , Gases/chemistry , Solvents/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Isotope Labeling/methods , Kinetics , Phase Transition
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