RESUMEN
Oxidative stress has recently been reported to assume a significant role in the pathophysiology of bipolar disorder. Several studies have demonstrated the replenishment of glutathione (GSH) diminishes oxidative cellular damage and ameliorates depressive symptoms in this disorder. Whilst the mechanism by which GSH exerts any clinical effect is unknown it has been proposed that it involves the bolstering of antioxidant defences by increasing the bioavailability of GSH, which in turn reverses clinical symptoms of depression. Such a proposal is predicated on the implicit assumption that GSH is diminished in these patients prior to GSH supplementation. However hitherto no study has reported in vivo measures of GSH in patients with bipolar disorder. Using magnetic resonance spectroscopy we obtained in vivo measures of GSH in young people with bipolar disorder and contrasted these with matched healthy controls. Young people with bipolar disorder were found to have no diminution in baseline GSH concentration and, furthermore, no significant correlations were found between GSH and clinical scores of depression or mania. The results do not support the hypothesis that oxidative stress is involved in the primary pathophysiology of bipolar disorder.
Asunto(s)
Trastorno Bipolar/metabolismo , Glutatión/metabolismo , Adolescente , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Trastorno Bipolar/patología , Estudios de Casos y Controles , Femenino , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Escalas de Valoración Psiquiátrica , Adulto JovenRESUMEN
The expansion of aquaculture and the recent development of more intensive land-based marine farms require efficient and cost-effective systems for treatment of highly nutrient-rich saline wastewater. Constructed wetlands with halophytic plants offer the potential for waste-stream treatment combined with production of valuable secondary plant crops. Pilot wetland filter beds, constructed in triplicate and planted with the saltmarsh plant Salicornia europaea, were evaluated over 88 days under commercial operating conditions on a marine fish and shrimp farm. Nitrogen waste was primarily in the form of dissolved inorganic nitrogen (TDIN) and was removed by 98.2 ± 2.2% under ambient loadings of 109-383 µmol l(-1). There was a linear relationship between TDIN uptake and loading over the range of inputs tested. At peak loadings of up to 8185 ± 590 µmol l(-1) (equivalent to 600 mmol N m(-2) d(-1)), the filter beds removed between 30 and 58% (250 mmol N m(-2) d(-1)) of influent TDIN. Influent dissolved inorganic phosphorus levels ranged from 34 to 90 µmol l(-1), with 36-89% reduction under routine operations. Dissolved organic nitrogen (DON) loadings were lower (11-144 µmol l(-1)), and between 23 and 69% of influent DON was removed during routine operation, with no significant removal of DON under high TDIN loading. Over the 88-day study, cumulative nitrogen removal was 1.28 mol m(-2), of which 1.09 mol m(-2) was retained in plant tissue, with plant uptake ranging from 2.4 to 27.0 mmol N g(-1) dry weight d(-1). The results demonstrate the effectiveness of N and P removal from wastewater from land-based intensive marine aquaculture farms by constructed wetlands planted with S. europaea.
Asunto(s)
Biodegradación Ambiental , Chenopodiaceae/metabolismo , Nitrógeno/farmacocinética , Salinidad , Plantas Tolerantes a la Sal/metabolismo , Aguas Residuales/química , Purificación del Agua/métodos , Acuicultura/métodos , Chenopodiaceae/crecimiento & desarrollo , Fósforo/farmacocinética , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Estadísticas no ParamétricasRESUMEN
Lower body mass index (BMI) and lower circulating leptin levels have been reported in girls with AIS. In this paper we evaluate skeletal sizes and asymmetries by higher and lower BMI subsets about the means for each of three groups of girls age 11-18 years: 1) normals, 2) school screening referrals, and 3) preoperative girls. Higher and lower BMI subsets, likely to have separated subjects with higher from those with lower circulating leptin levels, identify: 1) girls with relatively earlier and later menarche; 2) trunk width size greater in the higher than in the lower BMI subset, of all three groups; 3) abnormal upper arm length (UAL) asymmetries (right minus left) in the lower BMI subset of the preoperative girls; and 4) in thoracic AIS of screened and preoperative girls, Cobb angle and apical vertebral rotation each significantly and positively correlate with UAL asymmetry in the lower BMI subset but not in the higher BMI subset. In preoperative girls, the lower BMI subset shows the combination of relatively reduced pelvic width and abnormal UAL asymmetry, suggesting that both are linked to lower circulating leptin levels. An earlier puberty with hormonal changes provides a plausible explanation for the larger trunk width at the shoulders and pelvis especially at the younger ages in the higher BMI subsets. At the shoulders, this widening is driven by the ribcage which, in human evolution was acquired with decoupling of head and trunk movements required for efficient bipedal gait. The UAL asymmetry patterns within the groups and BMI subsets are not explained by hormonal mechanisms. It is hypothesized that 1) normal trunk widening of the thoracic cage by hormones in human adolescence is supplemented via the sympathetic nervous system under leptin-hypothalamic control influenced by energy stores (metabolic fuel); and 2) hypothalamic dysfunction with altered hypothalamic sensitivity to leptin through a SNS-driven asymmetric effect may create skeletal length asymmetries in upper arms, ribs, ilia and vertebrae, and initiate AIS. Additional mechanisms acting in the spine and trunk may be required for AIS to progress including 1) somatic nervous system dysfunction, 2) biomechanical spinal growth modulation, and 3) osteopenia.
Asunto(s)
Hipotálamo/patología , Leptina/fisiología , Menarquia/fisiología , Escoliosis/fisiopatología , Maduración Sexual/fisiología , Esqueleto , Sistema Nervioso Simpático/fisiología , Adolescente , Antropometría , Niño , Femenino , Humanos , Proyectos Piloto , Radiografía , Valores de Referencia , Factores de Riesgo , Escoliosis/diagnóstico por imagen , Factores Sexuales , Vértebras TorácicasRESUMEN
Recent efforts to use fMRI to investigate the effects of acupuncture needle manipulation on the brain have yielded discrepant results. This study was designed to test the reliability of fMRI signal changes evoked by acupuncture stimulation. Six subjects participated in six identical scanning sessions consisting of four functional scans, one for each of the four conditions: electroacupuncture stimulation (2 Hz) at GB 37, UB 60, non-acupoint (NP), and a control task of the finger tapping. In the group analysis across all subjects and sessions, both the average ratings on a Subjective Acupuncture Sensation Scale and the average fMRI signal changes (increases and decreases) were similar for GB37, UB 60, and NP. Visual inspection of the activation maps from individual sessions and ICC analysis revealed that fMRI signal changes evoked by electroacupuncture stimulation were significantly more variable than those from the control finger-tapping task. The relatively large variability across different sessions within the same subject suggests multiple sessions should be used to accurately capture the activation patterns evoked by acupuncture stimulation at a particular point for a specific subject.
Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Electroacupuntura/métodos , Potenciales Evocados/fisiología , Imagen por Resonancia Magnética/métodos , Adulto , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The "Neurobiological Correlates of Acupuncture" Conference was convened November 17-18, 2005 in Bethesda, Maryland. The conference was sponsored by the National Center for Complementary and Alternative Medicine (NCCAM) of the National Institutes of Health (NIH), U.S. Department of Health and Human Services (DHHS). Its goals were to encourage exchange of ideas regarding the direction of neuroimaging in acupuncture research as well as to discuss some of the challenges in this field. The use of neuroimaging, a relatively recent advance in the study of acupuncture, holds the promise of localizing and characterizing brain activity associated with acupuncture interventions in real time and in a minimally invasive way. Among the main challenges to research into the biological mechanisms of acupuncture are the multiple treatment variables and the difficulties of selecting appropriate experimental controls. Despite these challenges, numerous findings from acupuncture neuroimaging experiments were presented and discussed at the conference on topics related to possible signaling networks, sham acupuncture controls, acupoint specificity, acupuncture analgesia, acupuncture-associated brain response, and the potential for using neuroimaging in conjunction with translational and clinical acupuncture research. Future directions in acupuncture neuroimaging research, as recommended by conference participants, should focus on (1) continuing exploration of acupuncture signaling networks; (2) establishing standards and recommendations for performing and reporting acupuncture neuroimaging results; (3) enabling data sharing in the acupuncture neuroimaging community; (4) gaining a better understanding of placebo and control groups in acupuncture neuroimaging experiments; and (5) developing biomarkers that relate to physiologically and/or clinically relevant acupuncture responses to neuroimaging results.
Asunto(s)
Terapia por Acupuntura/normas , Investigación Biomédica/organización & administración , Técnicas de Diagnóstico Neurológico , Terapia por Acupuntura/métodos , Ensayos Clínicos como Asunto/normas , Medicina Basada en la Evidencia , Humanos , Sociedades Médicas , Estados UnidosRESUMEN
In this study, a well established expectancy manipulation model was combined with a novel placebo intervention, a validated sham acupuncture needle, to investigate the brain network involved in placebo analgesia. Sixteen subjects completed the experiment. We found that after placebo acupuncture treatment, subjective pain rating reduction (pre minus post) on the placebo-treated side was significantly greater than on the control side. When we calculated the contrast that subtracts the functional magnetic resonance imaging (fMRI) signal difference between post-treatment and pretreatment during pain application on placebo side from the same difference on control side [e.g., placebo (post - pre) - control (post - pre)], significant differences were observed in the bilateral rostral anterior cingulate cortex (rACC), lateral prefrontal cortex, right anterior insula, supramarginal gyrus, and left inferior parietal lobule. The simple regression (correlation) analysis between each subject's fMRI signal difference of post-treatment and pretreatment difference on placebo and control side and the corresponding subjective pain rating difference showed that significant negative correlation was observed in the bilateral lateral/orbital prefrontal cortex, rACC, cerebellum, right fusiform, parahippocampus, and pons. These results are different from a previous study that found decreased activity in pain-sensitive regions such as the thalamus, insula, and ACC when comparing the response to noxious stimuli applied to control and placebo cream-treated areas of the skin. Our results suggest that placebo analgesia may be configured through multiple brain pathways and mechanisms.
Asunto(s)
Analgesia por Acupuntura/psicología , Mapeo Encefálico , Cultura , Imagen por Resonancia Magnética , Dolor/fisiopatología , Efecto Placebo , Adulto , Cerebelo/fisiología , Corteza Cerebral/fisiología , Imagen Eco-Planar , Femenino , Antebrazo , Giro del Cíngulo/fisiología , Calor , Humanos , Masculino , Dimensión del Dolor , Giro Parahipocampal/fisiología , Lóbulo Parietal/fisiología , Puente/fisiología , Corteza Prefrontal/fisiologíaRESUMEN
The main physical properties of ferroelectric crystals are described, and the macroscopic and microscopic viewpoints are discussed along with some applications, such as in capacitors and nonlinear optics. The emphasis is on physical understanding, while the mathematical level is kept to a minimum or supplemented by graphical representations to make the article more accessible.
Asunto(s)
Biofisica/métodos , Hierro/química , Electricidad Estática , Cristalización , Iones , Modelos Teóricos , Temperatura , Termodinámica , Factores de TiempoRESUMEN
On 6 June 2000, the Medical Devices Agency (MDA) recommended that all Trilucent (soya-bean-oil filled) breast implants should be removed. This accelerated a trend that had already begun in our unit. This study follows our previous report on a 3 year series of women with Trilucent breast implants. The aim was to present our operative findings at explantation, and to correlate them with the preoperative signs and symptoms, the postoperative complications and the details of the hospital stay. In total, 44 patients (82 implants) underwent explantation, of whom 34 were cosmetic cases and 10 were reconstructive. Five patients had their implants removed before the MDA announcement. Implant rippling was the most common problem reported (25%), followed by pain (18%), implant deflation (9.1%) and capsular contracture (4.5%). Free oil was seen around the implant in 15 cases; four of these presented with clinical deflation, and three with rippling. The remaining eight patients were asymptomatic. We conclude that these implants tend to bleed, as evidenced by the presence of free oil around the implant in 34% of patients. The absence of free oil in 73% of the patients who presented with rippling suggests that the leaking oil is often metabolised and absorbed. The findings of this study are significant for women in whom free oil was found around the implant during explantation, and for those who still have Trilucent implants in place, for whatever reason, in spite of the MDA recommendation.
Asunto(s)
Implantes de Mama , Remoción de Dispositivos , Adulto , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Falla de Prótesis , Estudios Retrospectivos , Aceite de SojaRESUMEN
Thalassemia remains a significant health problem in Europe, the Middle East, and Asia. In such patients, generally high iron levels make free oxygen radicals accessible, for example, through Fenton-type chemistry, and generate superoxide and hydroxyl radicals. Increased oxygen radical capacity is known to be associated with cancer and ageing. It was shown in previous studies that peripheral blood lymphocytes from a sickle/beta thal double heterozygote-sickle phenotype, thalassemia patient, not yet on chelation therapy, were more sensitive to the effects of oxygen radicals and iron salts than lymphocytes from normal controls. Iron overload in thalassemia patients can result from dietary absorption. It was considered that with other dietary agents, such as food mutagens and flavonoids, the thalassemia patient might also show increased sensitivity to the effects of these agents. The present study, therefore, compared the effects of the food mutagen/carcinogen, 3-amino-1-methyl-5H-pyrido(4,3-b)indole (Trp-P-2), in fresh or frozen normal human peripheral lymphocytes with frozen lymphocytes from the same thalassemia patient. The lymphocytes from the thalassemia patient showed an approximately two-fold increase in sensitivity. When a combination of Tryp-P-2, with either quercitin or kaempferol, was compared in frozen lymphocytes and lymphocytes from the thalassemia patient, a two-fold increase in sensitivity was also maintained. Responses to Trp-P-2 were reduced to untreated control levels at the highest doses of quercitin and kaempferol, and were highly significantly different by comparison with Trp-P-2 alone (P<0.001). The flavonoids acted in an antigenotoxic/antioxidant manner. Sensitivity was slightly increased with kaempferol by comparison with quercitin. At low concentrations of the flavonoids there was some evidence of an exacerbation of response, perhaps due to a switch to pro-oxidant status. This exacerbation of response at low doses of flavonoids has been seen in earlier studies with normal lymphocytes. Teratogenesis Carcinog. Mutagen. 21:165-174, 2001.
Asunto(s)
Carbolinas , Quelantes/efectos adversos , Ensayo Cometa/métodos , Flavonoides/efectos adversos , Quempferoles , Linfocitos/efectos de los fármacos , Mutágenos , Talasemia/genética , Talasemia/metabolismo , Carcinógenos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Hierro/metabolismo , Quercetina/efectos adversos , Quercetina/análogos & derivados , Sensibilidad y EspecificidadRESUMEN
The role of the Lotus japonicus LjSym4 gene during the symbiotic interaction with Mesorhizobium loti and arbuscular mycorrhizal (AM) fungi was analyzed with two mutant alleles conferring phenotypes of different strength. Ljsym4-1 and Ljsym4-2 mutants do not form nodules with M. loti. Normal root hair curling and infection threads are not observed, while a nodC-dependent deformation of root hair tips indicates that nodulation factors are still perceived by Ljsym4 mutants. Fungal infection attempts on the mutants generally abort within the epidermis, but Ljsym4-1 mutants allow rare, successful, infection events, leading to delayed arbuscule formation. On roots of mutants homozygous for the Ljsym4-2 allele, arbuscule formation was never observed upon inoculation with either of the two AM fungi, Glomus intraradices or Gigaspora margarita. The strategy of epidermal penetration by G. margarita was identical for Ljsym4-2 mutants and the parental line, with appressoria, hyphae growing between two epidermal cells, penetration of epidermal cells through their anticlinal wall. These observations define a novel, genetically controlled step in AM colonization. Although rhizobia penetrate the tip of root hairs and AM fungi access an entry site near the base of epidermal cells, the LjSym4 gene is necessary for the appropriate response of this cell type to both microsymbionts. We propose that LjSym4 is required for the initiation or coordinated expression of the host plant cell's accommodation program, allowing the passage of both microsymbionts through the epidermis layer.
Asunto(s)
Fabaceae/genética , Fabaceae/microbiología , Hongos/fisiología , Genes de Plantas , Raíces de Plantas/microbiología , Plantas Medicinales , Rhizobium/fisiología , Simbiosis , Alelos , Pared Celular/microbiología , Pared Celular/ultraestructura , Hongos/crecimiento & desarrollo , Genes Recesivos , Mutación , Fenotipo , Raíces de Plantas/citología , Raíces de Plantas/ultraestructura , Rhizobium/crecimiento & desarrolloRESUMEN
Impairment of haemoglobin synthesis occurs in the genetic diseases known as thalassaemia. The consequent chronic anaemia leads to increased dietary iron absorption which results in iron overload. Treatment through regular blood transfusions increases oxygen capacity, but also adds iron from haemoglobin. An essential treatment, in parallel with transfusions, is the use of chelating agents to remove the excess iron. Thalassaemia patients are particularly at risk of free radical damage. Human lymphocytes from normal individuals can be investigated in vitro as a model system in the presence of free radicals in the Comet assay. This assay measures DNA damage, particularly DNA strand breakage. We examined cells from an Australian thalassaemic patient (sickle/beta thal double heterozygote-sickle phenotype) who had not yet received chelation therapy to determine if the cells were more sensitive to simulated iron overload and to haemosiderins. Lymphocytes from the patient were received as frozen samples after 28 h on dry ice and then placed in liquid nitrogen. Normal lymphocytes frozen under the same conditions and normal nonfrozen lymphocytes were compared. The lymphocytes from a normal female did not respond in vitro to ferric chloride (FeCl(3)) or haemosiderin but did to ferrous chloride (FeCl(2)) and ferrous sulphate (FeSO(4)). Deferoxamine appeared to reduce the response to FeCl(2) and FeSO(4) but deferiprone did not. When the lymphocytes from the nonchelated patient were treated with FeSO(4) and hydrogen peroxide, deferoxamine and deferiprone both reduced the response. Over the same dose range of iron salt (FeSO(4)), the lymphocytes from the thalassaemic patient were more sensitive, with much higher background levels of damage and induced damage. When deferiprone and deferoxamine were compared over a nontoxic range, deferiprone appeared to produce a greater reduction of damage in lymphocytes of the thalassaemia patient. Ferritin iron appears to be more available than haemosiderin iron in reactions leading to DNA damage. Haemosiderin containing higher amounts of the goethite-like (alpha-FeOOH) iron oxide phase leads to lower levels of DNA damage.
Asunto(s)
Quelantes/farmacología , Deferoxamina/farmacología , Compuestos Férricos/farmacología , Compuestos Ferrosos/farmacología , Hemosiderina/metabolismo , Linfocitos/efectos de los fármacos , Piridonas/farmacología , Bazo/patología , Talasemia beta/metabolismo , Australia , Transfusión Sanguínea , Cloruros , Ensayo Cometa , Daño del ADN , Deferiprona , Femenino , Ferritinas/metabolismo , Humanos , Linfocitos/metabolismo , Linfocitos/patología , Masculino , Valores de Referencia , Bazo/metabolismo , Talasemia beta/patología , Talasemia beta/terapiaRESUMEN
The process of converting renewable lignocellulosic biomass to ethanol requires a number of steps, and pretreatment is one of the most important. Pretreatment usually involves a hydrolysis of the easily hydrolyzed hemi-cellulosic component of biomass using some form of thermal/chemical/mechanical action that results in a product that can be further hydrolyzed by cellulase enzymes (the cellulosic portion). The sugars produced can then be fermented to ethanol by fermentative microorganisms. If the pretreatment step is not severe enough, the resultant residue is not as easily hydrolyzed by the cellulase enzyme. More severe pretreatment conditions result in the production of degradation products that are toxic to the fermentative microorganism. In this article, we report the quantitative analysis of glucose, mannose, xylose, and acetic acid using Fourier transform infrared (FTIR) spectroscopy on liquors from dilute-acid-pretreated soft-wood and hard-wood slurries. Comparison of FTIR and high-performance liquid chromatography quantitative analyses of these liquors are reported. Recent developments in infrared probe technology has enabled the rapid quantification of these sugars by FTIR spectroscopy in the batch reactor during optimization of the pretreatment conditions, or interfaced to the computer controlling a continuous reactor for on-line monitoring and control.
Asunto(s)
Biomasa , Celulosa/química , Lignina/química , Monosacáridos/análisis , Celulasa , Fermentación , Hidrólisis , Extractos Vegetales/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , MaderaRESUMEN
Ferritin and hemosiderin isolated from human thalassemic tissues have been characterized by infrared spectroscopy. Spectral features due to both the organic components and the inorganic iron oxyhydroxide have been identified. In particular, spectral evidence for the presence of the goethite (alpha-FeOOH) form of hemosiderin has been obtained in the < 800 cm(-1) range. Various treatments of the hemosiderin isolates result in only small changes in the infrared spectrum indicating the close association of the organic components with the nanoscale iron particles present.
Asunto(s)
Compuestos Férricos/análisis , Ferritinas/química , Hemosiderina/química , Talasemia beta/metabolismo , Ferritinas/aislamiento & purificación , Hemosiderina/aislamiento & purificación , Humanos , Hierro/análisis , Hígado/química , Fósforo/análisis , Sensibilidad y Especificidad , Espectrofotometría Infrarroja/métodos , Bazo/químicaRESUMEN
Thalassaemia is a group of genetic diseases where haemoglobin synthesis is impaired. This chronic anaemia leads to increased dietary iron absorption, which develops into iron overload pathology. Treatment through regular transfusions increases oxygen capacity but also provides iron through the red cells' haemoglobin. An essential treatment, in parallel with transfusions, is the use of chelating agents to remove the excess iron deposited in tissues. These deposits are found in the liver, spleen, heart, and pancreas and are associated with cardiac failure and diabetes. The deposits in these tissues of patients have been isolated as haemosiderin. Thalassaemia patients are particularly at risk of free radical induced damage. Thus, the present study has investigated, as a model system, human cells in vitro in the Comet assay in the presence of free radicals. This assay measures DNA damage, particularly DNA strand breakage. The effects of iron overload on cells oxidatively stressed with hydrogen peroxide (H(2)O(2)) have been determined as well as the effect of the chelating agent, deferoxamine. Iron overload was simulated with ferric (FeCl(3)) and ferrous chloride (FeCl(2)), ferrous sulphate (FeSO(4)) and haemosiderins. Both human lymphocytes from a male and a female donor and human adenocarcinoma colonic cells showed an increase in DNA damage in the Comet assay after treatment with H(2)O(2). Ferric chloride produced an increase in DNA damage in human colonic cells, but little or no damage in human lymphocytes. Ferrous chloride also produced weak DNA damage in human lymphocytes, but ferrous sulphate produced a dose-related response. Deferoxamine produced no DNA damage. When H(2)O(2) was combined with FeCl(3), FeCl(2), or FeSO(4), the DNA damage produced was as least as great as or slightly greater than with H(2)O(2) alone. When deferoxamine was combined with H(2)O(2) and FeSO(4) there was a consistent decrease in response. There was little or no decrease in response when deferoxamine was combined with H(2)O(2) and FeCl(3) or FeCl(2), but at high (100-300microm) doses there were changes in the appearance of cellular DNA from Comet tails to dense centres surrounded by a diffuse area. This was probably as a consequence of chelation processes. Haemosiderin produced no damage. The three fractions of haemosiderin examined were of three different densities and from a Thai patient where the oxyhydroxide phase is the ferrihydrite. The colour change was similar to that for FeCl(3), but the level of the ferric ion in the haemosiderin was possibly too low in the sample to produce a response. The next stage is to examine peripheral lymphocytes from thalassaemic patients, with and without chelation therapy, whose cells may be more sensitive to simulated iron overload and to lower levels of haemosiderin. Teratogenesis Carcinog. Mutagen. 20:11-26, 2000.
Asunto(s)
Daño del ADN/efectos de los fármacos , Hemosiderina/análisis , Compuestos de Hierro/farmacología , Especies Reactivas de Oxígeno , Talasemia/metabolismo , Células CACO-2 , Cloruros , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Femenino , Compuestos Férricos/farmacología , Compuestos Ferrosos/farmacología , Humanos , Peróxido de Hidrógeno/farmacología , Linfocitos/citología , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Masculino , Talasemia/genéticaRESUMEN
Percutaneous repair of the ruptured tendo Achillis has a low rate of failure and negligible complications with the wound, but the sural nerve may be damaged. We describe a new technique which minimises the risk of injury to this nerve. The repair is carried out using three midline stab incisions over the posterior aspect of the tendon. A No. 1 nylon suture on a 90 mm cutting needle approximates the tendon with two box stitches. The procedure can be carried out under local anaesthesia. We reviewed 27 patients who had a percutaneous repair at a median interval of 35 months after the injury. They returned to work at four weeks and to sport at 16. One developed a minor wound infection and another complex regional pain syndrome type II. There were no injuries to the sural nerve or late reruptures. This technique is simple to undertake and has a low rate of complications.
Asunto(s)
Tendón Calcáneo/lesiones , Tendón Calcáneo/cirugía , Traumatismos en Atletas/cirugía , Adolescente , Adulto , Anciano , Anestesia General , Anestesia Local , Articulación del Tobillo/fisiopatología , Moldes Quirúrgicos , Procedimientos Quirúrgicos Dermatologicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Rotura/cirugía , Técnicas de SuturaRESUMEN
Female Porton rats were loaded with iron either by supplementing the diet with 2.5% carbonyl iron for up to 22 months (18 rats) or by regularly injecting rat blood cells intraperitoneally for up to 10 months (eight rats). 57Fe Mössbauer spectroscopy of freeze-dried samples of liver and spleen was used to analyse the chemical forms of iron deposited in these tissues over the period of iron loading. A sextet signal in the Mössbauer spectra was identified as being due to a form of haemosiderin based on the structure of the mineral goethite. The spectral parameters of the sextet signal in the rat tissues indicate that the goethite-like haemosiderin particles are less crystalline than those found in iron-loaded human tissues. For the dietary-iron-loaded rat livers, the fraction (Fs) of the Mössbauer signal in the form of this sextet was found to increase significantly (from approx 0.04 to 0.09) with the age of the rats (r=0.77, P<0.0005). This indicates that the fraction of liver iron in the form of the goethite-like haemosiderin increases with age of the rat and hence with the duration of iron loading. In addition, Fs for these livers was found to increase significantly with the fraction of iron in non-parenchymal cells as measured by computer-assisted morphometric analysis of histological sections (r=0.71, P<0.005).
Asunto(s)
Compuestos Férricos/metabolismo , Hierro/administración & dosificación , Hígado/metabolismo , Bazo/metabolismo , Animales , Dieta , Eritrocitos , Femenino , Compuestos Férricos/química , Histocitoquímica , Hierro/análisis , Ratas , Espectrofotometría Atómica , Espectroscopía de MossbauerRESUMEN
Mössbauer spectra of 12 beta-thalassemia/hemoglobin E spleen samples from Thai patients who had not received multiple blood transfusions and chelation therapy and seven beta-thalassemia spleen samples from Australian patients who had received multiple blood transfusions and chelation therapy were recorded with sample temperatures of 78 K. Each spectrum was found to consist of a superposition of a relatively intense central doublet characteristic of high-spin Fe(III), a low intensity sextet of peaks due to magnetic hyperfine-field splitting, and occasionally a doublet that could be attributed to heme iron. A significant (P=0.01) difference (Kolmogorov-Smirnov statistic of 0.71) between the distributions of sextet signal intensity as a fraction (Fs) of the total non-heme iron Mössbauer spectral signal for the two groups of patients was detected. The distribution of Fs for the Thai beta-thalassemia/hemoglobin E spleens had a mean value of 0.128 (S.D. 0.035) while that for the Australian beta-thalassemia spleens had a mean of 0.27 (S.D. 0.12). No significant difference between the distributions of non-heme iron concentrations in the tissues for the two groups of patients was detected by atomic absorption spectrometry. This study shows that the Australian beta-thalassemia patients had a higher fraction of their non-heme spleen iron in a goethite-like form than the Thai beta-thalassemia/Hb E patients.
Asunto(s)
Compuestos Férricos/química , Hemoglobina E , Hemoglobinuria/metabolismo , Bazo/química , Talasemia beta/metabolismo , Terapia por Quelación , Transfusión de Eritrocitos , Hemoglobinuria/complicaciones , Hemoglobinuria/terapia , Humanos , Compuestos de Hierro/química , Minerales , Espectroscopía de Mossbauer , Talasemia beta/complicaciones , Talasemia beta/terapiaRESUMEN
Pregnancy is rarely complicated by aldosteronism. We report the case of a 32-year-old woman who became pregnant soon after primary aldosteronism was diagnosed. Only antihypertensive medication and oral potassium supplementation were required in addition to routine prenatal care. A healthy female infant was delivered at term. In this case, no adrenal adenoma was identified. We discuss management of aldosteronism in pregnancy and review the literature.