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1.
Sci Rep ; 13(1): 9082, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37277418

RESUMEN

This study tested progesterone for perimenopausal hot flush ± night sweat (vasomotor symptom, VMS) treatment. It was a double-blind, randomized trial of 300 mg oral micronized progesterone@bedtime versus placebo for 3-months (m) after a 1-m untreated baseline during 2012/1-2017/4. We randomized untreated, non-depressed, screen- and baseline-eligible by VMS, perimenopausal women (with flow within 1-year), ages 35-58 (n = 189). Participants aged 50 (± SD = 4.6) were mostly White, educated, minimally overweight with 63% in late perimenopause; 93% participated remotely. The 1° outcome was 3rd-m VMS Score difference. Participants recorded VMS number and intensity (0-4 scale)/24 h on a VMS Calendar. Randomization required VMS (intensity 2-4/4) of sufficient frequency and/or ≥ 2/week night sweat awakenings. Baseline total VMS Score (SD) was 12.2 (11.3) without assignment difference. Third-m VMS Score did not differ by therapy (Rate Difference - 1.51). However, the 95% CI [- 3.97, 0.95] P = 0.222, did not exclude 3, a minimal clinically important difference. Women perceived progesterone caused decreased night sweats (P = 0.023) and improved sleep quality (P = 0.005); it decreased perimenopause-related life interference (P = 0.017) without increased depression. No serious adverse events occurred. Perimenopausal night sweats ± hot flushes are variable; this RCT was underpowered but could not exclude a minimal clinically important VMS benefit. Perceived night sweats and sleep quality significantly improved.


Asunto(s)
Perimenopausia , Progesterona , Femenino , Humanos , Sudor , Posmenopausia , Sofocos/tratamiento farmacológico , Canadá
2.
Mol Pharm ; 16(1): 41-48, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30359037

RESUMEN

In an earlier investigation, ketoconazole (KTZ)-organic acid coamorphous systems were prepared, wherein, in the solid-state, there was ionic and/or hydrogen bonding interactions between the drug and the acid ( Fung , M. ; Berzins , K. ; Suryanarayanan , R. Mol. Pharmaceutics , 2018 , 15 ( 5 ), 1862 -1869 ). While the coamorphous systems accelerated KTZ dissolution, the organic acids were not effective in maintaining supersaturation, and drug precipitation was observed. Ternary drug-polymer-acid amorphous solid dispersions (ASDs) were prepared with KTZ, polyvinylpyrrolidone (PVP), and each oxalic (OXA), tartaric (TAR), citric (CIT), or succinic (SUC) acid. When compared with amorphous KTZ, solid dispersions of KTZ-PVP exhibited a moderate reduction in molecular mobility and small improvement in dissolution performance. The incorporation of acid (OXA, TAR, or CIT) in PVP-KTZ solid dispersion led to orders of magnitude increase in α-relaxation times and decrease in the crystallization propensity. These ternary ASDs were stable while crystallization of the cocrystal was observed in the SUC system. Moreover, the addition of acids also dramatically improved the dissolution performance of KTZ, a result attributed to KTZ-acid interactions.


Asunto(s)
Ácidos/química , Cetoconazol/química , Compuestos Orgánicos/química , Cristalización , Estabilidad de Medicamentos , Microscopía Electrónica de Rastreo , Estructura Molecular , Ácido Oxálico/química , Povidona/química , Ácido Succínico/química , Tartratos/química , Difracción de Rayos X
3.
Mol Pharm ; 15(5): 1862-1869, 2018 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-29528656

RESUMEN

In an earlier investigation, coamorphous systems of ketoconazole (KTZ) prepared with each oxalic (OXA), tartaric (TAR), citric (CIT), and succinic (SUC) acid, revealed drug-acid ionic or hydrogen bonding interactions in the solid-state (Fung et al, Mol. Pharmaceutics, 2018, 15 (3), 1052-1061). We showed that the drug-acid interactions in KTZ-TAR were the strongest, followed by KTZ-OXA, KTZ-CIT, and KTZ-SUC. In this study, we investigated the crystallization propensity and dissolution behavior of the KTZ-acid coamorphous systems. When in contact with water (either as water vapor or as aqueous phosphate buffer), while KTZ-CIT and KTZ-TAR were physically stable and resisted crystallization, KTZ-SUC and KTZ-OXA crystallized more readily than KTZ alone. The dissolution performances of the coamorphous systems were compared using the area under the curve (AUC) obtained from the concentration-time profiles. KTZ-OXA exhibited the highest AUC, while it was about the same for KTZ-TAR and KTZ-CIT and the lowest for KTZ-SUC. The enhancement in dissolution appeared to become more pronounced as the strength of the acid (OXA > TAR > CIT > SUC) increased. Coamorphization with acid caused at least a two-fold increase in AUC when compared with amorphous KTZ. The decrease in pH of the diffusion layer of the dissolving solid, brought about by the acid, is at least partially responsible for the dissolution enhancement. In addition, the particles of KTZ-OXA, KTZ-TAR, and KTZ-CIT were much smaller than those of KTZ-SUC. The consequent effect on surface area could be another contributing factor to the initial dissolution behavior.


Asunto(s)
Ácidos/química , Cetoconazol/química , Área Bajo la Curva , Cristalización/métodos , Difusión , Enlace de Hidrógeno , Solubilidad , Agua/química
4.
Mol Pharm ; 15(3): 1052-1061, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29309158

RESUMEN

The use of excipients other than polymers for enhancing the physical stability of amorphous active pharmaceutical ingredients (APIs) has largely been unexplored. We investigated several organic acids (oxalic, tartaric, citric, and succinic acid) for the purpose of stabilizing a weakly basic API, ketoconazole (KTZ), in the amorphous state. Coamorphous systems with each acid, in 1:1 KTZ-acid molar ratio, were prepared by spray drying. The interaction of KTZ with each acid was investigated by FT-IR, solid-state NMR, and quantum chemical calculations. Each acid exhibited ionic and/or hydrogen-bonding interactions with KTZ, and quantum chemical calculations provided a measure of the strength of this interaction. The α-relaxation times, a measure of molecular mobility, were determined by dielectric spectroscopy, and their crystallization propensity by variable temperature X-ray powder diffractometry. Crystallization was observed only in two systems, KTZ-oxalic salt and KTZ-succinic as a cocrystal. An increase in the strength of KTZ-acid interaction translated to a decrease in molecular mobility. When the two systems prepared with structurally similar dicarboxylic acids (succinic and oxalic acid) were compared, the physical stability enhancement of KTZ-oxalic coamorphous system could be attributed to its lower mobility. However, the exceptional stability of KTZ-tartaric and KTZ-citric could not be explained by mobility alone, indicating that structural factors may also contribute to stabilization. The interaction between KTZ and acid may alter the system sufficiently so that the crystallization propensity of the KTZ-acid complex (salt or cocrystal) becomes relevant. We conclude that small molecule excipients have the potential to improve the physical stability of amorphous APIs.


Asunto(s)
Composición de Medicamentos/métodos , Excipientes/química , Cetoconazol/química , Rastreo Diferencial de Calorimetría , Ácido Cítrico/química , Cristalización , Desecación , Ácidos Dicarboxílicos/química , Estabilidad de Medicamentos , Enlace de Hidrógeno , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Difracción de Rayos X
5.
Skinmed ; 15(5): 385-386, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29139370

RESUMEN

A 79-year-old Chinese man presented with a 2-month history of pruritic, tender ulceration covering his perianal region. He was initially treated with oral amoxicillin/clavulanic acid and vancyclovir, with no improvement. His history included hypertension. On physical examination, there was a 1.5-cm solitary, pink shallow ulcer with a tender erythematous base on the right side of the buttock cleft (Figure 1).


Asunto(s)
Antituberculosos/uso terapéutico , Úlcera Cutánea/microbiología , Tuberculosis Cutánea/tratamiento farmacológico , Tuberculosis Cutánea/microbiología , Anciano , Canal Anal , Pueblo Asiatico , Nalgas , Quimioterapia Combinada , Etambutol/uso terapéutico , Humanos , Isoniazida/uso terapéutico , Masculino , Mycobacterium , Pirazinamida/uso terapéutico , Rifampin/uso terapéutico , Úlcera Cutánea/patología , Tuberculosis Cutánea/patología
7.
J Comp Neurol ; 523(16): 2372-89, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25921658

RESUMEN

Tooth loss is common, and exploring the neuroplastic capacity of the face primary motor cortex (face-M1) and adjacent primary somatosensory cortex (face-S1) is crucial for understanding how subjects adapt to tooth loss and their prosthetic replacement. The aim was to test if functional reorganization of jaw and tongue motor representations in the rat face-M1 and face-S1 occurs following tooth extraction, and if subsequent dental implant placement can reverse this neuroplasticity. Rats (n = 22) had the right maxillary molar teeth extracted under local and general anesthesia. One month later, seven rats had dental implant placement into healed extraction sites. Naive rats (n = 8) received no surgical treatment. Intracortical microstimulation (ICMS) and recording of evoked jaw and tongue electromyographic responses were used to define jaw and tongue motor representations at 1 month (n = 8) or 2 months (n = 7) postextraction, 1 month postimplant placement, and at 1-2 months in naive rats. There were no significant differences across study groups in the onset latencies of the ICMS-evoked responses (P > 0.05), but in comparison with naive rats, tooth extraction caused a significant (P < 0.05) and sustained (1-2 months) decreased number of ICMS-defined jaw and tongue sites within face-M1 and -S1, and increased thresholds of ICMS-evoked responses in these sites. Furthermore, dental implant placement reversed the extraction-induced changes in face-S1, and in face-M1 the number of jaw sites even increased as compared to naive rats. These novel findings suggest that face-M1 and adjacent face-S1 may play a role in adaptive mechanisms related to tooth loss and their replacement with dental implants.


Asunto(s)
Implantes Dentales , Corteza Motora/fisiopatología , Plasticidad Neuronal/fisiología , Corteza Somatosensorial/fisiopatología , Pérdida de Diente/fisiopatología , Pérdida de Diente/terapia , Animales , Mapeo Encefálico , Modelos Animales de Enfermedad , Electromiografía , Potenciales Evocados , Maxilares/fisiopatología , Masculino , Diente Molar/fisiopatología , Diente Molar/cirugía , Distribución Aleatoria , Ratas Sprague-Dawley , Lengua/fisiopatología
9.
Transplantation ; 91(3): 373-8, 2011 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-21258272

RESUMEN

BACKGROUND: The effect of islet cell transplantation (ICT) on the progression of diabetic microvascular complications is not well understood. METHODS: We have conducted a prospective, crossover, cohort study comparing ICT with intensive medical therapy on the progression of diabetic nephropathy, retinopathy, and neuropathy. RESULTS: The rate of decline in glomerular filtration rate is slower after ICT than on medical therapy. There was significantly more progression of retinopathy in medically treated patients than post-ICT. There was a nonsignificant trend for improved nerve conduction velocity post-ICT. CONCLUSIONS: ICT is associated with less progression of microvascular complications than intensive medical therapy. Multicenter, randomized trials are needed to further study the role of ICT in slowing the progression of diabetic complications.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/terapia , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/prevención & control , Progresión de la Enfermedad , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos , Adulto , Estudios de Cohortes , Estudios Cruzados , Angiopatías Diabéticas/fisiopatología , Nefropatías Diabéticas/epidemiología , Neuropatías Diabéticas/epidemiología , Retinopatía Diabética/epidemiología , Femenino , Humanos , Hipoglucemiantes/uso terapéutico , Incidencia , Masculino , Microvasos/fisiopatología , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento
10.
BMJ Case Rep ; 20112011 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-22691586

RESUMEN

Type III hyperlipoproteinemia (type III HLP) rarely manifests in childhood. Long-term follow-up (37 years) of the first patient revealed hypothyroidism at diagnosis requiring thyroxine replacement, palmar xanthomas requiring surgical removal, splenomegaly requiring splenectomy, 18 episodes of pancreatitis and premature coronary artery disease. Investigation revealed an apolipoprotein E phenotype of E2/E2 and partial lipoprotein lipase deficiency. Investigation of the second patient revealed a combination of apoE2/E2 phenotype and heterozygous familial hypercholesterolaemia. The third patient had a complete deficiency of lipoprotein lipase activity, an abnormal thyroid stimulating hormone on diagnosis (with subsequent normalisation without treatment), and apoE2/E2 phenotype. Type III HLP is a serious disorder with lifelong consequences of premature vascular disease and recurrent pancreatitis. Early presentation of disease in our patients was associated with additional precipitating factors. Drug treatment of paediatric type III HLP is indicated if dietary modifications alone are insufficient in managing the dyslipidaemia.


Asunto(s)
Hiperlipoproteinemia Tipo III , Niño , Femenino , Estudios de Seguimiento , Humanos , Hiperlipoproteinemia Tipo III/diagnóstico , Hiperlipoproteinemia Tipo III/terapia , Masculino , Persona de Mediana Edad
11.
BMJ Case Rep ; 20102010.
Artículo en Inglés | MEDLINE | ID: mdl-22242078

RESUMEN

A 72-year-old man at high risk for cardiovascular disease, with a history of peripheral vascular disease and type 2 diabetes, presented with lipids above targets despite maximum daily treatment with atorvastatin 80 mg, fenofibrate supra 160 mg daily, and ezetimibe 10 mg. His low density lipoprotein cholesterol (LDL-C) was 2.6 mmol/l, total cholesterol: HDL ratio 5.6, and high density lipoprotein cholesterol (HDL-C) 0.9 mmol/l. Because his lipids were not within target, he was advised to start 2250 mg of niacin in three divided doses daily. For 5 months, he mistakenly took 2250 mg of niacin three times daily, a consumption of 6750 mg/day! The effects on his lipids were: HDL-C increased nearly 100% to 1.7 mmol/l, LDL-C decreased by 50% to 1.3 mmol/l, and cholesterol: HDL ratio decreased by over 50% to 2.1. His excessive intake dramatically demonstrates the positive effect of niacin on lipids. Fortunately he did not suffer adverse effects from taking more than the recommended limit of 3000 mg/day.

12.
Transplantation ; 86(12): 1762-6, 2008 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-19104418

RESUMEN

BACKGROUND: We hypothesized that transplantation of islets into type 1 diabetics could improve outcomes of glucose metabolism, renal function, retinopathy, and neuropathy compared with intensive medical therapy. METHODS: We conducted a prospective, crossover, cohort study of intensive medical therapy (group 1) versus islet cell transplantation (group 2) in 42 patients. All were enrolled in group 1 then 31 crossed over with group 2 when islet donation became available. Transplantation was performed by portal venous embolization of more than 12,000 islet equivalents/kg body weight under cover of immunosuppression with antithymocyte globulin, tacrolimus, and mycophenolate. Outcome measures were HbA1c, change in glomerular filtration rate (GFR), progression of retinopathy, and change in nerve conduction velocity. This report details interim analysis of outcomes after 34+/-18 months (group 1) and 38+/-18 months (group 2). RESULTS: HbA1c (%) in group 1 was 7.5+/-0.9 versus 6.6+/-0.7 in group 2 (P<0.01). GFR (mL/min/month) declined in both groups (group 1 -0.45+/-0.7 vs. group 2 -0.12+/-0.7, P=0.1). Slope of the GFR decline in group 1 was significantly more than 0. Retinopathy progressed in 10 of 82 eyes in group 1 versus 0 of 51 in group 2 (P<0.01). Nerve conduction velocity (m/sec) remained stable in group 1 (47.8+/-5 to 47.1+/-5 m/sec) and group 2 (47.2+/-4.5 to 47.7+/-3.5). CONCLUSION: Islet transplantation yields improved HbA1c and less progression of retinopathy compared with intensive medical therapy during 3 years follow-up.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/cirugía , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos/fisiología , Adulto , Anciano , Estudios de Cohortes , Estudios Cruzados , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/fisiopatología , Neuropatías Diabéticas/fisiopatología , Retinopatía Diabética/fisiopatología , Progresión de la Enfermedad , Estudios de Seguimiento , Tasa de Filtración Glomerular/efectos de los fármacos , Tasa de Filtración Glomerular/fisiología , Hemoglobina Glucada/metabolismo , Humanos , Pruebas de Función Renal , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Adulto Joven
13.
Transplantation ; 85(10): 1400-5, 2008 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-18497678

RESUMEN

BACKGROUND: Diabetic retinopathy is a major complication of type 1 diabetes and remains a leading cause of visual loss. There have been no comparisons of the effectiveness of intensive medical therapy and islet cell transplantation on preventing progression of diabetic retinopathy. METHODS: The British Columbia islet transplant program is conducting a prospective, crossover study comparing medical therapy and islet cell transplantation on the progression of diabetic retinopathy. Progression was defined as the need for laser treatment or a one step worsening along the international disease severity scale. An interim data analysis was performed after a mean 36-month follow-up postislet transplantation and these results are presented. RESULTS: The medical and postislet transplant groups were similar at baseline. Subjects after islet transplantation had better glucose control than the medically treated subjects (mean HbA1c 6.7%+/-0.9% vs. 7.5+/-1.2, P<0.01) and were C-peptide positive. Progression occurred significantly more often in all subjects in the medical group (10/82 eyes, 12.2%) than after islet transplantation (0/51 eyes, 0%) (P<0.01). Considering only subjects who have received transplants, progression occurred in 6/51 eyes while on medical treatment and 0/51 posttransplant (P<0.02). CONCLUSIONS: Progression of diabetic retinopathy was more likely to occur during medical therapy than after islet cell transplantation.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/cirugía , Retinopatía Diabética/prevención & control , Retinopatía Diabética/fisiopatología , Trasplante de Islotes Pancreáticos/fisiología , Adulto , Anciano , Estudios de Cohortes , Estudios Cruzados , Progresión de la Enfermedad , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Edema Macular/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Agudeza Visual
14.
J Youth Adolesc ; 37(6): 736-746, 2008 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25152546

RESUMEN

This cross-sectional study examined relationships between pubertal development, depressive symptoms and delinquency in a sample of 241 males and 213 females aged 9-13 years. Four objectives were set forth for this study: 1) to examine relationships between pubertal stage or timing and depressive symptoms and delinquency; 2) to compare continuous and categorical measures of pubertal timing; 3) to examine gender as a moderator of these relationships, and 4) to examine maltreatment as a moderator of these relationships. Results indicated that mature pubertal stage and early (continuous) pubertal timing were both related to higher delinquency whereas only early pubertal timing was related to depressive symptoms. Categorical timing was not related to depressive symptoms or delinquency. Neither gender nor maltreatment were found to be moderators. These findings provide evidence against equating pubertal stage, continuous timing, and categorical timing, and highlight the need to identify possible moderators in research on pubertal development.

15.
Transplantation ; 84(1): 17-22, 2007 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-17627232

RESUMEN

BACKGROUND: The effect of islet cell transplantation (ICT) on renal function in type 1 diabetes is uncertain and some recent studies report a significant decline in estimated glomerular filtration rate (GFR) and worsening of albuminuria. METHODS: We are conducting a prospective crossover study comparing medical treatment with islet transplantation on the progression of diabetic complications, including renal function. The primary endpoint is change in GFR measured by Tc-diethylenetriaminepentaacetate with secondary endpoints including estimated GFR and albumin excretion. RESULTS: We have followed 21 patients after islet transplantation a median of 29 months (range 13-45) and compared their results with medically treated patients followed a median 29.5 months (range 13-56). There is no difference in the rate of decline in measured GFR between medically treated patients (-0.35+/-0.89; 95% CI: -0.57 to -0.13 mL/min/month/1.73 m) and those after ICT (-0.31+/-1.18; 95% CI: -0.61 to -0.01) and neither is significantly different from that expected for the general population. The rate of decline in our estimated GFR results is lower than that reported in other studies and we did not find any worsening of albuminuria. CONCLUSIONS: We do not find evidence of worsening of renal function after islet transplantation compared with medically treated patients.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/fisiopatología , Hipoglucemiantes/uso terapéutico , Trasplante de Islotes Pancreáticos , Adulto , Anciano , Albuminuria/fisiopatología , Glucemia/metabolismo , Estudios de Cohortes , Estudios Cruzados , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/orina , Progresión de la Enfermedad , Femenino , Tasa de Filtración Glomerular , Humanos , Riñón/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Prospectivos
17.
Transplantation ; 83(1): 24-8, 2007 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17220786

RESUMEN

BACKGROUND: Islet transplantation can reduce or eliminate the need for insulin in patients with type 1 diabetes. Exenatide is a long acting analogue of Glucagon-like peptide-1 (GLP-1) that augments glucose induced insulin secretion, and may increase beta cell mass. We evaluated the effect of exenatide on insulin secretion after islet transplantation. METHODS: Eleven C-peptide positive islet cell recipients with elevated glucose levels were treated with exenatide for three months. Response was assessed by insulin requirements, meal tolerance tests, and hyperglycemic glucose clamps. RESULTS: Ten patients responded to exenatide. Two patients who had not restarted insulin achieved good glycemic control and one patient who had received 5500 IE/kg in first islet infusion was able to stop insulin. Seven other patients decreased their insulin dose by 39% on exenatide. Hyperglycemic clamp studies showed a rise in second phase insulin release (before exenatide: 246+/-88 pM; during exenatide: 644+/-294 pM, P<0.01). Meal tolerance studies before and one month after stopping exenatide did not show a difference in glucose or C-peptide values. Nausea and vomiting were the major side effects. CONCLUSIONS: Exenatide stimulates insulin secretion in islet transplant recipients. It reduces insulin dose in some patients and may delay the need to resume insulin in others. We did not find any evidence of a trophic effect on islets.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Hipoglucemiantes/uso terapéutico , Trasplante de Islotes Pancreáticos/fisiología , Péptidos/uso terapéutico , Ponzoñas/uso terapéutico , Adulto , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Exenatida , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Inyecciones Subcutáneas , Insulina/uso terapéutico , Masculino , Persona de Mediana Edad , Péptidos/administración & dosificación , Ponzoñas/administración & dosificación
18.
Diabetes Res Clin Pract ; 74(2): 189-93, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16621111

RESUMEN

Islet transplantation can improve glycemic control in patients with type 1 diabetes and reduce or eliminate the need for insulin. Glucagon-like peptide-1 (GLP-1) is an intestinal insulinotropic hormone that augments glucose induced insulin secretion, and has a trophic effect on beta-cells. We evaluated the effect of GLP-1 on insulin secretion after islet transplantation. Patients underwent hyperglycemic glucose clamp studies 1 month after their last transplant. GLP-1 was infused during the second hour of the hyperglycemic clamp. Results were compared to normal control subjects and patients with type 2 diabetes who underwent an identical hyperglycemic clamp. First phase insulin release was absent in patients, while second phase insulin was not significantly reduced (control: 118+/-29 pM; type 2 diabetes: 68+/-20 pM; transplant: 99+/-18 pM, p=ns for all). GLP-1 had a significant incretin effect on transplanted islets but the response was less than controls (control: 2108+/-344 pM; type 2 diabetes: 929+/-331 pM; transplant: 329+/-112 pM, p<0.0001 control versus transplant). Islet transplant patients had no evidence of resistance to insulin mediated glucose disposal. We conclude that transplanted islets retain the ability to respond to GLP-1.


Asunto(s)
Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 1/cirugía , Péptido 1 Similar al Glucagón/farmacología , Trasplante de Islotes Pancreáticos/fisiología , Islotes Pancreáticos/fisiología , Fragmentos de Péptidos/farmacología , Adulto , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Dieta para Diabéticos , Femenino , Técnica de Clampeo de la Glucosa , Humanos , Insulina/metabolismo , Secreción de Insulina , Masculino , Persona de Mediana Edad , Péptidos/farmacología
19.
Arch Surg ; 140(8): 735-44, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16103282

RESUMEN

HYPOTHESIS: A local multiorgan donor pancreas procurement program can provide a source for optimized isolation of purified viable islets for transplantation into patients with type 1 diabetes mellitus receiving best medical therapy. DESIGN: Prospective before-after cohort study. SETTING: Tertiary referral center. PATIENTS: Glycemic control was assessed in 10 patients with diabetes-induced renal dysfunction who were enrolled in a best medical therapy program and then crossed over to islet transplantation. INTERVENTIONS: Thirty human pancreata were retrieved from local multiorgan donors and consecutively processed with intraductal collagenase perfusion, continuous digestion, and density gradient purification (group 1, n = 9) or similarly processed but impure tissue fractions cultured in vitro and then repurified to retrieve additional islets (group 2, n = 21). Islets were implanted by percutaneous portal embolization, providing more than 10 000 islet equivalents (IE) per kilogram of body weight (infusions from 1-3 donors per patient) under cover of antithymocyte globulin, sirolimus, or mycophenolate mofetil and tacrolimus. MAIN OUTCOME MEASURES: Islet yields, purity, and cell viability (caspase 3, terminal deoxynucleotidyl transferase-mediated biotin-deoxyuridine 5-triphosphate nick-end labeling stain, and insulin secretion in vitro) were compared. In patients, monitored metabolic parameters were C-peptide secretion, insulin requirements, glycemic excursion, and hemoglobin A(1c) (HbA(1c)). RESULTS: For group 1 vs group 2, no differences were observed in pancreas age (43 vs 44 years), cold storage (5 vs 4 hours), or weight (73 vs 82 g). Group 2 yielded 453 690 IE vs 214 109 IE in group 1 (P = .002). Grafts contained 50% or more endocrine cells in both groups. No difference occurred in cell viability or insulin secretion. Islets from 90% of group 2 pancreata met release criteria for transplantation. C-peptide secretion was detected in all recipients and persisted with a median follow-up to 12 months (range, 6-21 months) after full islet transplantation. Daily insulin dependence was reversed in all patients for at least 3 months. Five patients resumed small insulin doses. Compared with the best care program, all patients had improved metabolic stability. The mean +/- SE HbA(1c) level at entry into the study was 7.8% +/- 0.5%, and this decreased to 6.9% +/- 0.2% after best care (P = .38) and further to 6.2% +/- 0.2% at 6 months after transplantation (P = .002 vs entry; P = .15 vs best care; analysis of variance). CONCLUSIONS: Local pancreas donor retrieval with islet isolation and culture conditioning enabled an offer of islets for transplantation for 90% of consecutively processed pancreata. Isolated islets secreted insulin during prolonged follow-up after implantation into patients, yielding metabolic control comparable with that achieved by best medical therapy.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/cirugía , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos/métodos , Islotes Pancreáticos/citología , Inmunología del Trasplante/fisiología , Adulto , Análisis de Varianza , Glucemia/análisis , Estudios de Cohortes , Diabetes Mellitus Tipo 1/diagnóstico , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Supervivencia de Injerto , Humanos , Trasplante de Islotes Pancreáticos/efectos adversos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Probabilidad , Estudios Prospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Recolección de Tejidos y Órganos , Resultado del Tratamiento
20.
J Abnorm Psychol ; 114(2): 187-96, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15869350

RESUMEN

This study tests the hypothesis that psychopathy-prone adolescents show reduced anticipatory skin conductance responding. Electrodermal activity was recorded while participants anticipated and responded to a 105 dB signaled or unsignaled white-noise burst. Using an extreme groups design, the authors used Child Psychopathy Scale (D. R. Lynam, 1997) scores from a community sample of 335 male adolescents (age 16) to form control (n = 65) and psychopathy-prone (n = 65) groups. Significantly more psychopathy-prone participants were nonresponders in the signaled anticipatory (p = .014), signaled responsivity (p = .037), and unsignaled responsivity (p = .003) conditions compared with controls. Anticipatory hyporesponsivity of psychopathy-prone adolescents similar to the electrodermal hyporesponsivity found in psychopathic adults suggests that this autonomic impairment is present by adolescence and may predispose individuals to adult psychopathy.


Asunto(s)
Trastorno de Personalidad Antisocial/diagnóstico , Respuesta Galvánica de la Piel/fisiología , Estrés Psicológico/psicología , Estimulación Acústica , Adolescente , Adulto , Factores de Edad , Trastorno de Personalidad Antisocial/prevención & control , Trastorno de Personalidad Antisocial/psicología , Percepción Auditiva/fisiología , Susceptibilidad a Enfermedades/diagnóstico , Susceptibilidad a Enfermedades/psicología , Humanos , Delincuencia Juvenil/psicología , Masculino , Ruido/efectos adversos , Psicología del Adolescente , Tiempo de Reacción/fisiología
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