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1.
Arch Razi Inst ; 77(4): 1497-1502, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36883148

RESUMEN

Mycobacterium Tuberculosis (TB) is one of the serious bacterial infections that cause diseases and may lead to death. In this study, 178 individuals were examined for TB infection at Baghdad TB center during the period from 15th January to 1st October 2021. Out of 178 participants, 73 were shown to be positive for TB infection, while 105 showed negative results. According to the results, there was no significant variation between infected males and females with TB in comparison to the control group (P>0.05). The results showed that the mean age of the patients for both males and females was in the range of 2-65 years. Additionally, there were significant differences in patients with TB compared to the control group in terms of the weight loss of 8.82 ± 6.75 Kg, red blood cell (RBC) count (3.43 ± 0.56) × 106/µl, white blood cell (WBC) count (3.12 ± 1.57) × 106/µl, platelet count (1.03 ± 0.56) × 106/µl, and hemoglobin level (6.66 ± 1.34) g/dl. A total of 30 TB patients and 50 normal individuals were genotyped to detect the IL-1ß rs 114534 gene. The polymerase chain reaction (PCR) was used for exon amplification in region 5 of the ILB1 gene in the TB patients by using specific primers. The finding showed that there was an amplified product of 249bp located in chromosome 2q13-14. A total of 30 TB patients and 50 normal individuals were also genotyped to detect the IL-6 rs 1800795 gene. The PCR was used for amplification of the IL-6 gene in TB patients by using specific primers. The finding showed that there was an amplified product of 431 bp located in chromosome 7p15-p2. The expression of the ILB1 gene was investigated in TB patients and healthy controls by using qPT-PCR. Results showed that there was a high Ct value for patients and controls with a high Ct value of templates, preoperational to the total ribonucleic acid (RNA) concentration and gene expression. The expression of the IL-6 gene was investigated in TB patients and healthy controls by using qPT-PCR. Our findings revealed a high Ct value for patients and controls with a high Ct value of templates, preoperational to the total RNA concentration and gene expression.


Asunto(s)
Interleucinas , Mycobacterium tuberculosis , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Cartilla de ADN , Genotipo , Interleucina-6/genética , Interleucina-6/inmunología , Irak/epidemiología , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/inmunología , ARN , Interleucinas/genética , Interleucinas/inmunología
2.
Asian Pac J Cancer Prev ; 17(1): 261-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26838221

RESUMEN

BACKGROUND: Breast cancer is the leading cause of cancer death among women and the second in humans worldwide. Many published studies have suggested an association between MDR1 polymorphisms and breast cancer risk. Our aim was to study the association between genetic polymorphism of MDR1 at three sites (C3435T, G2677A/T, and C1236T) and their haplotype and the risk of breast cancer in Jordanian females. MATERIALS AND METHODS: A case-control study involving 150 breast cancer cases and 150 controls was conducted. Controls were age-matched to cases. The polymerase chain reaction/restriction fragment length polymorphism (PCR- RFLP) technique and sequencing were performed to analyse genotypes. RESULTS: The distribution of MDR1 C3435T genotypes differed between cases and controls [cases, CC 45.3%, CT 41.3%, and TT 13.3%; controls, CC 13.4%, CT 43.3%, and TT 30.2%, p < 0.001]. Similarly, the distribution of G2677A/T significantly differed [cases, GG 43.1 %, GT+GA 50.9% and AA+TT 6%; controls, GG 29.6 %, GT+GA 50.9%, and AA+TT 19.4%, p = 0.004]. On the other hand, genotype and allelotype distribution of C1236T was not statistically different between cases and controls (p=0.56 and 0.26, respectively). The CGC haplotype increased the risk to breast cancer by 2.5-fold compared to others, while TGC and TTC haplotypes carried 2.5- and 5-fold lower risk of breast cancer, respectively. CONCLUSIONS: Genetic polymorphisms of MDR1 C3435T and G2677A/T, but not C1236T, are associated with increased risk of breast cancer. In addition, CGC, TGC and TTC haplotypes have different impacts on the risk of breast cancer. Future, larger studies are needed to validate these findings.


Asunto(s)
Neoplasias de la Mama/etiología , Neoplasias de la Mama/genética , Predisposición Genética a la Enfermedad/genética , Haplotipos/genética , Polimorfismo de Longitud del Fragmento de Restricción/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Alelos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Incidencia , Jordania , Persona de Mediana Edad
3.
Ann Pharm Fr ; 74(1): 21-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26530448

RESUMEN

The comparative pharmacokinetic behavior of albendazole (ABZ) and its new benzimidazol prodrug [1-tert-butyloxycarbonyl-5-propylthio-1-H-benzimidazol-2ylcarbamate of methyl] (ABZBoc), following their oral administration (10mg/kg) to healthy dogs was explored. Blood samples were obtained serially over a 24h period after treatment, then the plasma was analyzed by high-performance liquid chromatography (HPLC) to search the albendazole metabolites (ABZSO and ABZSO2). However, the albendazole parent drug was not detectable at any time after both treatments (ABZ and ABZBoc). By albendazole metabolites (ABZSO and ABZSO2) were the analytes recovered in the plasma after oral administration of ABZ and ABZBoc. Furthermore, some amounts of ABZBoc were also available in the plasma samples treated with this new produg. The plasma profile of each analyte followed a similar pattern after both treatments, the active metabolite (ABZSO) was the major analyte recovered in plasma (between 1 and 24h post-treatment). The pharmacokinetic parameters of both groups were calculated (Cmax, Tmax, t1/2, AUC0->∞), and analyzed using the Student's t-test, P<0.05. Thus,the pharmacokinetic analysis indicated four statistically significant changes in the pharmacokinetic parameters defined above of the albendazole metabolites (ABZSO, ABZSO2) between the group treated with albendazole (group A) and that treated with ABZBoc prodrug (group B). Hence, the levels of the various pharmacokinetics parameters were low in the group treated with prodrug, as well they did not reach equivalent concentrations to that of albendazole. These differences between albendazole and its new prodrug may be explained by the fact that ABZBoc prodrug was not effectively reduced in the intestine of dogs.


Asunto(s)
Albendazol/farmacocinética , Antihelmínticos/farmacocinética , Profármacos/farmacocinética , Albendazol/análogos & derivados , Animales , Perros , Masculino
4.
J Alzheimers Dis ; 11(1): 25-32, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17361032

RESUMEN

BACKGROUND: The concept that the neurotoxicity of amyloid beta protein could partly result from vascular effects that may be detected in peripheral microcirculation is new. METHODS: We compared peripheral endothelial vascular responses of patients with early clinically confirmed Alzheimer's disease (AD) to that of people with normal cognition and those with other forms of dementia. Acetylcholine (ACh) was iontophoresed into the skin and the resultant vasodilator response was measured using laser Doppler flowmetery. RESULTS: The ratio of ACh response to saline (ratio E/S) was determined. Mean +/- SEM of ratios E/S were 8.8 +/- 0.9 for controls (n=168), 1.4 +/- 0.1 for AD patients (n=80) and 3.1 +/- 0.5 for other dementia (n=84). Using the optimal cut-off point of E/S ratio of 1.9, an 80% diagnostic sensitivity and specificity for AD have been observed. When the control sample was filtered for those with cardiovascular diseases and with MMSE < 28, this improved the specificity to 90% (n=119). Furthermore, 15 subjects were randomly drawn from a longitudinal healthy ageing study. Five of those subjects met the criteria for mild cognitive impairment (MCI) after eight years of follow up using a battery of cognitive tests. When tested for their E/S ratio in a blind fashion, the skin test successfully identified those subjects. CONCLUSIONS: The results support our hypothesis that endothelial alterations can be detected early in the course of the disease. We suggest that this simple skin test could potentially be applied as diagnostic adjunct in patients with mild cognitive symptoms or those with early clinical evidence of AD.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Endotelio Vascular/fisiopatología , Acetilcolina , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/toxicidad , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/fisiopatología , Demencia/fisiopatología , Femenino , Humanos , Iontoforesis , Flujometría por Láser-Doppler , Masculino , Escala del Estado Mental , Microcirculación/fisiopatología , Valores de Referencia , Piel/irrigación sanguínea , Vasodilatación/fisiología
5.
Phlebology ; 22(2): 49-55, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18268849

RESUMEN

OBJECTIVES: Venous leg ulcers represent a major clinical problem, with poor rates of healing. Ideal treatment is compression bandaging. The effect of compression on neurovascular tissues involved in wound repair is unclear. This study aims to assess the effect of four-layer compression therapy (40 mmHg) on neurovascular function and wound healing in people with chronic venous leg ulcers--15 people (55 years or older) with venous leg ulcers for more than six weeks. METHODS: Basal microvascular perfusion measurement (MPM), oxygen tension (tcpO2) measured at sensor temperatures of 39 degrees C and 44 degrees C and sensory nerve function using electrical cutaneous perception thresholds (ECPT) at 5, 250 and 2000 Hz (corresponding to C, Adelta and Abeta fibres) were assessed adjacent to the ulcer site, and at a mirror location on the non-ulcerated limb. Testing was undertaken before and after therapy for 5-12 weeks of four-layer compression bandaging. RESULTS: There was significant improvement in tcpO2 at 44 degrees C and ECPT at 2000 Hz (P < 0.05) compared with pre-intervention. Changes in basal MPM, tcpO2 at 39 degrees C and ECPT at 5 and 250 Hz after compression therapy did not reach statistical significance. CONCLUSION: Four-layer compression bandaging in people with venous leg ulcers improved some components of neurovascularture in people with chronic venous leg ulcers. Whether this improvement has contributed to wound healing in this study requires further investigation.


Asunto(s)
Neovascularización Fisiológica , Medias de Compresión , Úlcera Varicosa/terapia , Cicatrización de Heridas , Anciano , Anciano de 80 o más Años , Enfermedad Crónica , Femenino , Humanos , Masculino , Microcirculación/fisiopatología , Persona de Mediana Edad , Oxígeno/metabolismo , Proyectos de Investigación , Células Receptoras Sensoriales/fisiopatología , Umbral Sensorial , Factores de Tiempo , Resultado del Tratamiento , Úlcera Varicosa/metabolismo , Úlcera Varicosa/fisiopatología
6.
Ann Dermatol Venereol ; 133(12): 979-84, 2006 Dec.
Artículo en Francés | MEDLINE | ID: mdl-17185928

RESUMEN

INTRODUCTION: Although not recommended in France at the consensus conference of 1994, routine monitoring of patients with stage I melanoma using imaging techniques is commonly carried out. The aim of this retrospective regional study was to define methods for diagnosing transition to the metastatic stage of melanoma. PATIENTS AND METHODS: This was a retrospective study based on questionnaires among dermatologists in the Champagne-Ardenne and southern Aisne regions of France. For each patient with stage IV melanoma between 1987 and 2002, data were collected concerning the primary melanoma (date of diagnosis, clinical picture, histopathologic features), stage of melanoma prior to diagnosis of metastatic melanoma and characteristics of the metastases (date, number, type, site and modern discovery: clinical signs or routine imaging). RESULTS: One hundred and eight patients (63 men and 45 women; mean age: 59 years) were included in the study. The predominant site of the primary melanoma was the trunk for men (n=31) and the lower limbs for women (n=16) and the mean Breslow index was 4.31 mm (SD=4.22), with histologic ulceration being present in 40% of cases. The mean time to transition to stage IV after discovery of the primary tumour was 2.8 years (SD=2.95). The modes of discovery of metastases comprised clinical examination (functional signs or physical examination) in 58 cases and routine imaging in 50 cases, with no significant differences based on whether patients were initially in stage I-II or in stage III. DISCUSSION: This study shows that over half of patients progressing to stage IV melanoma had a suspicious sign or clinical symptom, once again highlighting the importance of clinical monitoring. In contrast, many organ metastases, particularly pulmonary, were discovered by routine imaging examinations carried out as part of patient follow-up, although this is not currently recommended practice in France. CONCLUSION: The role of powerful imaging examinations such as scans, with constantly improving resolution, still remains to be defined in the follow-up of patients with stage I-II melanoma, and further prospective studies are thus required.


Asunto(s)
Melanoma/patología , Metástasis de la Neoplasia/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico por Imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Examen Físico , Estudios Retrospectivos
7.
Contact Dermatitis ; 53(4): 222-5, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16191020

RESUMEN

Nickel-elicited systemic contact dermatitis is a well-known entity, although it is far less common than allergic contact dermatitis. In most of the cases, the main way of nickel administration is oral. Clinical manifestations are miscellaneous including pompholyx, diffuse exanthema, flexural dermatitis or baboon syndrome. Systemic nickel dermatitis induced by venous catheters is very uncommon, but it is probably underdiagnosed. We report here 2 patients with diffuse recurrent maculopapular rash corresponding to nickel-elicited systemic contact dermatitis. They were both perfused during the last episode with the assistance of a peripheral polyurethane venous catheter during or just before the cutaneous eruption. At the base of the catheter, there was a small metallic eyelet on which dimethylglyoxime test was positive, indicating a release of nickel. Then, we measured nickel release in normal use conditions and found high nickel levels, although the manufacturer denied that nickel could be released. This diagnosis is important to know because such exanthema often occurred during postoperative or postpartum period. Its frequency is probably underestimated because it is often considered as a cutaneous drug reaction. To our knowledge, only 2 cases have been reported in the literature.


Asunto(s)
Cateterismo Periférico/efectos adversos , Cateterismo Periférico/instrumentación , Dermatitis Alérgica por Contacto/etiología , Níquel/efectos adversos , Oligoelementos/efectos adversos , Adulto , Diseño de Equipo , Femenino , Humanos , Pruebas del Parche , Poliuretanos
8.
Water Environ Res ; 76(4): 316-26, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15508422

RESUMEN

This paper will provide wastewater treatment utility professionals with a comprehensive synthesis of information pertinent to N-nitrosodimethylamine (NDMA) so that plant operators can make informed and cost-effective decisions regarding appropriate management techniques. A suspect disinfection byproduct, NDMA is a potential carcinogen and is presently under scrutiny from the U.S. Environmental Protection Agency because it poses a threat to groundwaters from reclaimed wastewaters. Recognizing that the current state of knowledge pertaining to the occurrence and treatment of NDMA from wastewater treatment is in its infancy, the information presented in this paper is timely and will help utility professionals develop confidence toward controlling NDMA during wastewater treatment. Given the increased probability of the formation of NDMA using current wastewater treatment technologies and also in the complex matrices of the wastewaters subjected to UV treatment, the investigation of occurrence pathways and means of suppression of NDMA formation before and after treatment needs to be investigated. This paper also summarizes strategies to minimize exposure such as modifying treatment or instituting waste and agricultural management practices that minimize inorganic and organic nitrogen discharges to wastewaters.


Asunto(s)
Desinfección , Nitrosaminas/análisis , Nitrosaminas/envenenamiento , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/análisis , Agricultura , Animales , Aductos de ADN , Dimetilnitrosamina , Humanos , Resinas de Intercambio Iónico , Hígado/patología , Medición de Riesgo , Roedores
9.
Mini Rev Med Chem ; 3(7): 785-7, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14529519

RESUMEN

The oceans are a source of a large group of structurally unique natural products that are mainly found in invertebrates such as sponges, tunicates, bryozoans, and molluscs. It is interesting to note that the majority of marine compounds currently in clinical trials or under preclinical evaluation are produced by these species rather than as secondary metabolites by marine algae. Through the combined efforts of marine natural products chemists and pharmacologists a number of promising compounds have been identified that are either already at advanced stages of clinical trials such as the new anti-cancer drug marine alkaloid ecteinascidin 743, or have been selected as promising candidates for extended preclinical evaluation. This is the case for conotoxins, (Table 1) where a number of conopeptides are currently being developed as analgesics for the treatment of neuropathic pain.


Asunto(s)
Bloqueadores de los Canales de Calcio/uso terapéutico , Conotoxinas/uso terapéutico , Dolor/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Animales , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/farmacología , Conotoxinas/química , Conotoxinas/farmacología , Humanos , Caracoles/química
10.
Biochemistry ; 42(22): 6904-11, 2003 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-12779345

RESUMEN

We describe the identification of a conopeptide sequence in venom duct mRNA from Conus victoriae that suppresses a vascular response to pain in the rat. PCR-RACE was used to screen venom duct cDNAs for those transcripts that encode specific antagonists of vertebrate neuronal nicotinic acetylcholine receptors (nAChRs). One of these peptides, Vc1.1, was active as an antagonist of neuronal nAChRs in receptor binding and functional studies in bovine chromaffin cells. It also suppressed the vascular responses to unmyelinated sensory nerve C-fiber activation in rats. Such vascular responses are involved in pain transmission. Furthermore, its ability to suppress C-fiber function was greater than that of MVIIA, an omega-conotoxin with known analgesic activity in rats and humans. Vc1.1 has a high degree of sequence similarity to the alpha-conotoxin family of peptides and has the 4,7 loop structure characteristic of the subfamily of peptides that act on neuronal-type nAChRs. The results suggest that neuronal alpha-conotoxins should be further investigated with respect to their potential to suppress pain.


Asunto(s)
Conotoxinas/genética , Conotoxinas/farmacología , Fibras Nerviosas Amielínicas/efectos de los fármacos , Neuronas Aferentes/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Bovinos , Células Cromafines/efectos de los fármacos , Células Cromafines/metabolismo , ADN Complementario/genética , Relación Dosis-Respuesta a Droga , Masculino , Datos de Secuencia Molecular , Fibras Nerviosas Amielínicas/fisiología , Unión Neuromuscular/efectos de los fármacos , Unión Neuromuscular/fisiología , Neuronas Aferentes/fisiología , Antagonistas Nicotínicos/farmacología , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Receptores Nicotínicos/fisiología , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , omega-Conotoxinas/farmacología
11.
Rev Med Liege ; 58(12): 751-6, 2003 Dec.
Artículo en Francés | MEDLINE | ID: mdl-14978849

RESUMEN

Urticaria is a transient eruption of erythematous or oedematous swelling of the dermis and is usually associated with itching which clinically is very easy to diagnose. However, it causes several etiological, pathophysiological and therapeutic problems. We will develop the acute and chronic urticaria as well as their different associations with systemic diseases. Some current data concerning chronic idiopathic autoimmune urticaria is reviewed. The management and therapeutics will be discussed.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Urticaria , Enfermedad Aguda , Enfermedad Crónica , Humanos , Urticaria/complicaciones , Urticaria/inmunología , Urticaria/fisiopatología , Urticaria/terapia
12.
Inflamm Res ; 51(6): 295-9, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12088270

RESUMEN

OBJECTIVE AND DESIGN: The aim of the present study was to examine the contribution of the two kinin receptors B1 and B2 to the increased blood flow observed in response to bradykinin (BK) in a blister model under different injury conditions. MATERIAL: Young male Sprague-Dawley rats weighing 250-350 g were used. METHODS: A vacuum-induced blister was raised in the rat hind paw and blood flow measured in the superfused blister base under four different conditions including, early phase acute injury; late phase acute injury; recurrent injury and early phase acute injury in the setting of chronic nerve damage. BK (10 microM) was superfused alone, or in the presence of the B1 antagonist DesArg9Leu8BK (DALBK), (10 nM) and/or the B2 antagonist [D-Arg,Hyp3,Thi5 D-Tic7,Oic8] Bradykinin (HOE 140) (10 nM). RESULTS: HOE 140 significantly inhibited the BK response in all models. Significant inhibition of BK-induced vasodilatation by DALBK was only observed in the late phase acute and recurrent injury models. CONCLUSIONS: The results suggest that the involvement of the inducible B1 receptor in skin inflammation site is related to the site, duration and recurrence of the injury condition.


Asunto(s)
Bradiquinina/análogos & derivados , Bradiquinina/farmacología , Dermatitis/etiología , Receptores de Bradiquinina/fisiología , Piel/irrigación sanguínea , Animales , Antagonistas de los Receptores de Bradiquinina , Dermatitis/fisiopatología , Masculino , Microcirculación , Nitroprusiato/farmacología , Ratas , Ratas Sprague-Dawley , Receptor de Bradiquinina B1 , Receptor de Bradiquinina B2 , Flujo Sanguíneo Regional/efectos de los fármacos
13.
J Invest Dermatol ; 117(4): 886-91, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11676828

RESUMEN

Previous studies using an antibody to cis-urocanic acid and mast-cell-depleted mice implicated both cis-urocanic acid and mast cells in the mechanisms by which ultraviolet B light suppresses systemic contact hypersensitivity responses in mice. In the absence of a direct stimulatory effect of cis-urocanic acid on connective tissue mast cells, an indirect association was investigated. A blister induced in the rat hind footpad was used to examine the effects of slowly perfused cis-urocanic acid on cutaneous blood flow. cis-Urocanic acid but not trans-urocanic acid increased microvascular flow by a mechanism largely dependent on the combined activity of the neuropeptides, substance P and calcitonin gene-related peptide. Perfusion of cis-urocanic acid over the base of blisters induced in sensory-neuropeptide-depleted rats did not have any stimulatory effect above that seen with perfusion of cis-urocanic acid together with neuropeptide receptor antagonists in control rats. There was a small direct effect of cis-urocanic acid on microvascular blood flow. As both substance P and calcitonin gene-related peptide could directly degranulate connective tissue mast cells, this study suggests that cis-urocanic acid indirectly activates mast cells via its effects on peripheral terminals of unmyelinated primary afferent sensory nerves. cis-Urocanic-acid-induced neuropeptides may also contribute to ultraviolet-B-induced cutaneous inflammation and alterations to Langerhans cell activity.


Asunto(s)
Neuropéptidos/metabolismo , Nervios Periféricos/metabolismo , Sensación/fisiología , Ácido Urocánico/farmacología , Animales , Vesícula/fisiopatología , Degranulación de la Célula , Dermatitis por Contacto/fisiopatología , Femenino , Miembro Posterior , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Ratones , Ratones Endogámicos BALB C , Microcirculación/efectos de los fármacos , Neuropéptidos/deficiencia , Cavidad Peritoneal/citología , Ratas , Ratas Sprague-Dawley , Piel/irrigación sanguínea , Estereoisomerismo , Rayos Ultravioleta
14.
Free Radic Biol Med ; 31(4): 430-9, 2001 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-11498276

RESUMEN

Using a reversible chronic constriction injury (CCI) model of neuropathic pain, we previously demonstrated that changes in thermal hyperalgesia correlate with the changes in peripheral microvascular blood flow in the affected paw, and that recovery can be assessed by normalization of both behavioral and vascular responses. Using the same model, this study examined age-related changes in recovery after nerve injury and the involvement of free radicals and nitric oxide (NO) in these changes. Four loose, nonconstrictive ligatures were applied to the sciatic nerve in the right, mid-thigh region of young and old (3 and 24 months) Sprague Dawley rats. All rats were monitored weekly (for 8-10 weeks) for their thermal threshold using a 46 degrees C water bath and some groups were used to examine endothelial and smooth muscle-dependent microvascular responses to substance P (SP) and sodium nitroprusside (SNP), respectively. These substances were perfused over the base of blisters raised on the footpad innervated by the injured nerve. Free radical activity in the sciatic nerve was assessed by measuring the activity of xanthine oxidase (XO) and lipid hydroperoxides (LPO). Young rats showed signs of recovery (reduction in thermal hyperalgesia and improvement of peripheral microvascular blood flow) from the fifth week. No signs of recovery were observed in old rats for 8 weeks, with some reduction in thermal hyperalgesia observed by weeks 9 and 10. XO activity was significantly higher in young injured nerves compared to sham (400%) and was even significantly greater in old injured nerves (680%). Similarly, old injured nerves showed 300% increase in LPO levels compared to sham. The role of reactive oxygen species (ROS) in delayed recovery in old rats was examined using the antioxidant tirilazad mesylate. Tirilazad (20 mg/kg) was injected intramuscularly (im) in the mid-thigh region starting on day 1 post CCI, (early treatment) or day 7 (late treatment). Levels of LPO in the injured sciatic nerves were significantly reduced using either early or late treatment, however tirilazad had opposing effects on recovery, prolonging or alleviating thermal hyperalgesia, respectively. The role of neuronal nitric oxide (nNO) was then examined using the specific neuronal nitric oxide synthase (nNOS) inhibitor, 3-bromo-7-nitroindazole (3Br-7NI) (10 mg/kg). 3Br-7NI resulted in a significant alleviation of thermal hyperalgesia with improvement in the vascular responses from weeks 5 and 6 onwards. A combination of 3Br-7NI and tirilazad treatment was also used but did not show an additive effect. The results suggest that ROS and nNO contribute to delayed recovery of injured nerves in old rats and to the maintenance of thermal hyperalgesia and the reduction in microvascular blood flow in the area innervated by the injured nerve. The results also raise the notion that possible interaction of free radicals with NO to form peroxynitrite might be responsible for such delayed recovery. Ironically, this study also reveals a positive role for free radicals in tissue repair and raises the notion that early intervention with antioxidants could exert a negative effect on repair of injured nerves.


Asunto(s)
Envejecimiento/fisiología , Radicales Libres , Óxido Nítrico/fisiología , Dolor/fisiopatología , Nervio Ciático/lesiones , Animales , Antioxidantes/farmacología , Enfermedad Crónica , Constricción Patológica , Calor , Hiperalgesia/fisiopatología , Peróxidos Lipídicos/metabolismo , Masculino , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo I , Dolor/etiología , Dolor/metabolismo , Pregnatrienos/farmacología , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno , Nervio Ciático/irrigación sanguínea , Nervio Ciático/efectos de los fármacos , Xantina Oxidasa/metabolismo
15.
J Gerontol A Biol Sci Med Sci ; 56(8): B356-63, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11487594

RESUMEN

During aging there is a decline in sensory nerve function that is associated with reduced neurogenic inflammation and poor wound repair. The cellular mechanism(s) responsible for this decline in function with age is not well understood. We previously reported that sensory nerves in aged rats release sensory neuropeptides preferentially in response to low-frequency (5 Hz) as compared with higher-frequency (15 Hz) antidromic electrical stimulation, and that low-frequency transcutaneous electrical nerve stimulation accelerates wound healing. The present study investigates possible mechanisms for this preferential response. Using laser Doppler techniques, we have measured changes in blood flow in the base of vacuum-induced blisters induced in the rat hind footpad of young and old animals in response to low-frequency (5 Hz) or high-frequency (15 Hz) electrical stimulation (20 V, 2 ms for 1 minute) of the sciatic nerve. The relative contributions of the sensory neuropeptides, substance P and calcitonin gene-related peptide (CGRP), and of N-type voltage-gated calcium channels to the vascular responses were assessed by using the specific receptor antagonists RP67580, which is 2-(1-imino-2-(2 methoxy phyenyl) ethyl)-7,7 diphenyl-4 perhydroisoindolone-(3aR, 7aR); CGRP(8-37); and omega-conotoxin GVIA (Conus geographus), respectively. The results showed a greater involvement of substance P at high-frequency electrical stimulation and of CGRP at low-frequency stimulation. Our finding that omega-conotoxin-sensitive N-type calcium channel function was preserved with age and was only involved in the vascular response to low-frequency electrical stimulation could explain our previous report demonstrating beneficial effects of low-frequency transcutaneous electrical nerve stimulation to wound repair in aged animals. The current results have important practical implications for improving tissue repair in the aged.


Asunto(s)
Envejecimiento/fisiología , Péptido Relacionado con Gen de Calcitonina/efectos de los fármacos , Neuropéptidos/antagonistas & inhibidores , Nervio Ciático/fisiología , Piel/irrigación sanguínea , Sustancia P/efectos de los fármacos , Vasodilatación/fisiología , omega-Conotoxinas/farmacología , Análisis de Varianza , Animales , Vesícula/fisiopatología , Velocidad del Flujo Sanguíneo , Péptido Relacionado con Gen de Calcitonina/biosíntesis , Canales de Calcio/efectos de los fármacos , Estimulación Eléctrica , Flujometría por Láser-Doppler , Masculino , Modelos Animales , Músculo Liso/fisiología , Neuropéptidos/farmacología , Ratas , Ratas Sprague-Dawley , Valores de Referencia , Células Receptoras Sensoriales/efectos de los fármacos , Sustancia P/biosíntesis , Vasodilatación/efectos de los fármacos , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
16.
Neurobiol Aging ; 22(4): 635-43, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11445264

RESUMEN

In rats, the function of sensory nerves in the hind limb declines significantly with age. Normally aging rats and rats treated neonatally with capsaicin were studied here. Quantification of vascular response and substance P in young (3 months) and old (24 months) rats showed additive effects of age and capsaicin treatment. The levels in dorsal root ganglion of a particular deletion in mitochondrial DNA (mtDNA(4834)) were about 300-fold higher in old compared to young rats. Capsaicin treatment had no significant effect on mtDNA(4834) abundance. Dorsal root ganglia of old (but not young) rats were found to contain a spectrum of multiple deletions. The abundance of mtDNA(4834) in dorsal root ganglia from individual rats correlated strongly with their decline in vascular function, even where vascular responses were systematically depressed due to prior capsaicin treatment. One possibility is that mitochondrial DNA mutations directly lead to functional decline at mitochondrial and tissue levels. Alternatively, loss of mitochondrial DNA integrity and physiological decline may be consequences of the same factor, such as oxidative stress.


Asunto(s)
Envejecimiento/fisiología , ADN Mitocondrial/genética , Ganglios Espinales/fisiopatología , Eliminación de Gen , Neuronas Aferentes/fisiología , Animales , Capsaicina/farmacología , Estimulación Eléctrica , Ganglios Espinales/química , Ganglios Espinales/citología , Miembro Posterior/irrigación sanguínea , Miembro Posterior/inervación , Masculino , Neuronas Aferentes/química , Neuronas Aferentes/efectos de los fármacos , Nitroprusiato/farmacología , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional/efectos de los fármacos , Flujo Sanguíneo Regional/fisiología , Nervio Ciático/citología , Nervio Ciático/fisiopatología , Sustancia P/análisis , Vasodilatadores/farmacología
17.
Free Radic Biol Med ; 30(1): 1-8, 2001 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11134890

RESUMEN

Following tissue injury, adequate inflammatory vascular responses are essential for subsequent tissue repair. The aims of this study were to investigate the role of reactive oxygen species (ROS, generated at the injury site) in modulating the inflammatory response under acute- and chronic-injury conditions. The effect of age and the implications of this modulation for tissue repair was investigated. Using laser Doppler flowmetry, inflammatory vascular responses were monitored in the base of vacuum-induced blisters in the hind footpad of anesthetized rats (65 mg/kg Nembutal). Inflammation was amplified by superfusion of substance P (SP) over the blister base. The inflammatory response was examined in acute blisters induced on either naïve skin (acute-injury model) or on skin innervated by a chronically injured nerve (chronic-injury model). Furthermore, the acute-injury model was examined during early and late phases, 0 and 5 h after blister induction, respectively. The involvement of ROS was assessed by either combined superfusion of the antioxidants: superoxide dismutase and catalase over the blister base in acute-injury, or intramuscular injection of tirilazad in chronically injured rats. The results showed that antioxidant treatment had no effect on the response during early and late phases of acute inflammation in young rats. However in old rats, the vascular response was significantly attenuated (60%) or significantly increased (40%) during the early and late phases of acute inflammation, respectively. Under chronic-injury conditions, antioxidant treatment significantly enhanced the response in both young and old rats. We then examined the effect of antioxidant, tirilazad, on the healing of a full thickness thermal injury induced in the intrascapular region (using a CO(2) laser) of the rat. Following burn injury, tirilazad was injected around the wound site starting on day 1 (early treatment) or day 6 (late treatment). Tirilazad had opposing actions on wound closure with early and late treatments delaying (24.6 +/- 0.6 d) or accelerating (14.2 +/- 0.3 d) wound closure compared with the group of aged controls (20.3 +/- 0.8 d). The results suggest that ROS have a paradoxical role exerting either a positive or negative effect on the inflammatory response with age. We contend that the role of ROS in modulating inflammation should be considered when designing treatment protocols to accelerate tissue repair.


Asunto(s)
Envejecimiento , Inflamación/fisiopatología , Especies Reactivas de Oxígeno/fisiología , Cicatrización de Heridas , Animales , Antioxidantes/farmacología , Vesícula/etiología , Vesícula/fisiopatología , Velocidad del Flujo Sanguíneo , Quemaduras/fisiopatología , Flujometría por Láser-Doppler , Masculino , Pregnatrienos/farmacología , Ratas , Ratas Sprague-Dawley , Sustancia P/farmacología , Succión
18.
Neurogastroenterol Motil ; 13(6): 575-84, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11903918

RESUMEN

We investigated the relationship between changes in small intestinal motility and changes in blood pressure and heart rate in response to intestinal distension. Rats were maintained under stable anaesthesia with alpha-chloralose, and jejunal motility, blood pressure and heart rate were recorded. Pressure changes during propagated contractions of the circular muscle were recorded in the jejunum when the intraluminal pressure was maintained at 10 mmHg. Raising the pressure in 10 mmHg increments from 10 mmHg to 40 mmHg increased the frequency of propagated contractions from 0.30 +/- 0.06 min-1 (mean +/- SEM) to 1.29 +/- 0.09 per min. In contrast, amplitudes of contractions above baseline pressure decreased from 19.5 +/- 0.6 mmHg to 7.8 +/- 0.5 mmHg. Simultaneously, blood pressure and heart rate were both increased. Pretreatment of rats with capsaicin, or severing the mesenteric nerves acutely, prevented these cardiovascular responses, but did not influence the changes in propagated activity caused by distension. Propagated contractions were blocked by hexamethonium (10 mg kg-1, intravenously [i.v.]) and by local application of 2% lidocaine, but propulsion was unchanged by hyoscine (1 mg kg-1, i.v.). Phentolamine (1 mg kg-1, i.v.) increased the frequency of propagated contractions. The methods described in this work allow the effects of drugs on intrinsic intestinal reflexes to be distinguished from their effects on extra-intestinal, pseudoaffective reflexes. In addition, unlike other experiments using anaesthetized rats, blood pressure increased in response to distension, as it does in mammals that are not anaesthetized. The experiments demonstrate that the neural pathways for propagated contractions that rely on intrinsic nerve circuits, including intrinsic primary afferent neurones, and the neural pathways for extrinsic reflexes that signal pain or discomfort in the intestine, which involve capsaicin-sensitive spinal afferent neurones, are independent.


Asunto(s)
Afecto/fisiología , Presión Sanguínea/fisiología , Intestinos/fisiología , Músculo Liso/fisiología , Antagonistas Adrenérgicos alfa/farmacología , Anestésicos Locales/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Capsaicina/farmacología , Frecuencia Cardíaca/fisiología , Intestinos/efectos de los fármacos , Lidocaína/farmacología , Mesenterio/inervación , Antagonistas Muscarínicos/farmacología , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso/efectos de los fármacos , Antagonistas Nicotínicos/farmacología , Dolor/fisiopatología , Dolor/psicología , Estimulación Física , Presión , Ratas , Ratas Sprague-Dawley , Reflejo/efectos de los fármacos , Reflejo/fisiología
19.
Arch Environ Health ; 55(5): 304-18, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11063405

RESUMEN

T-cell-derived antigen-binding molecules (TABMs) specific for benzoic acid were isolated from the serum of a toluene-sensitive patient. The resulting purified TABMs (BA-TABMs) did not contain immunoglobulin G and were associated with the cytokine transforming growth factor-beta (TGF-beta). BA-TABMs bound to benzoic acid conjugated to human serum albumin (BA-HSA), as well as to other chemicals conjugated to human serum albumin-including dinitrophenol and oxazolone. The binding of BA-TABMs to the conjugated chemicals increased the level of detectable TGF-beta, and a similar effect was observed with the unconjugated chemicals, benzoic acid and 2,4-dinitrophenol glycine. The increase in TGF-beta was critically dependent on the ratio between BA-TABMs and the conjugated or unconjugated chemicals; the increase was optimum at intermediate concentrations and absent at low and high concentrations. The authors used an established animal model in vivo and demonstrated that TGF-beta enhanced the inflammatory response induced by the release of neuropeptides from sensory nerves; this enhancement occurred in a dose-dependent manner. The BA-TABMs also enhanced this neurogenic inflammatory response in a dose-dependent manner, and this effect was blocked by anti-TGF-beta antibody. When the authors added either BA-HSA or benzoic acid, the effect of BA-TABMs on neurogenic inflammation was further enhanced at intermediate concentrations of antigen and was unaltered or reduced at higher concentrations. TABMs specific to particular chemicals, as a result of their association with cytokines (e.g., TGF-beta), may be implicated in symptom production in chemically sensitive patients.


Asunto(s)
Anticuerpos Monoclonales/análisis , Ácido Benzoico/farmacología , Hipersensibilidad/sangre , Hipersensibilidad/inmunología , Inmunoglobulina G/análisis , Neuropéptidos/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/sangre , Tolueno/efectos adversos , Factor de Crecimiento Transformador beta/metabolismo , Adulto , Animales , Sitios de Unión , Electroforesis en Gel de Poliacrilamida , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Inmunoglobulina G/inmunología , Masculino , Neuropéptidos/biosíntesis , Pruebas Neuropsicológicas , Ratas , Ratas Sprague-Dawley , Flujo Sanguíneo Regional/efectos de los fármacos , Nervio Ciático/fisiología , Piel/irrigación sanguínea , Especificidad de la Especie , Linfocitos T/inmunología , Tolueno/inmunología
20.
Int Contact Lens Clin ; 26(4): 84-91, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10996761

RESUMEN

Six fungal species (Fusarium sp, Exophiala jeanselmei, Penicillium spp, Aspergillus niger, Paecilomyces spp, and Alternaria spp) were used to inoculate soft contact lenses. Four types of soft lenses were used: high-water (58%) and low-water (38%) content lenses and lenses that were unworn or worn for 1 day. The fungi displayed a range of macroscopic and microscopic features that allowed differentiation of species. There was no statistically significant effect of lens water content on growth rate and only Penicillium spp showed significantly higher growth for worn versus unworn lenses. A number of the fungi showed secretions, thought to be enzymes, which potentially aid in the process of lens penetration.

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