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1.
Ann R Coll Surg Engl ; 106(6): 547-552, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38478048

RESUMEN

INTRODUCTION: Postoperative surgical hypoparathyroidism (PoSH) following thyroid surgery is an established complication. Several predictive factors have been identified including perioperative parathyroid hormone (PTH) levels. The aim of the study is to compare the drop in perioperative PTH to postoperative day 1 PTH in predicting hypocalcaemia and hypoparathyroidism. METHODS: Records of consecutive patients who had either total or completion thyroidectomy with or without central neck dissection in a 3-year period in a single thyroid surgery unit were accessed to retrieve data on demographics, pathology, surgery, perioperative biochemistry and management. RESULTS: Of 295 included patients, there were 227 (76.9%) females. Forty-five (15.3%) had completion thyroidectomy, and the rest had total thyroidectomy. Seventy-eight (26.4%) had concomitant central neck dissection. Sixty-four (21.7%) had hypocalcaemia on the day after surgery. Hypoparathyroidism persisted in 10.5% of patients at 6 months. Both day 1 PTH and a drop in PTH predicted day 1 hypocalcaemia (p < 0.001) and 6-month hypoparathyroidism (p < 0.001). The area under the receiver operating characteristic (ROC) curves for day 1 PTH and drop in PTH for the prediction of day 1 hypocalcaemia (0.729 vs 0.726, respectively) and for 6-month hypoparathyroidism (0.964 vs 0.958, respectively) were similar, albeit slightly better for day 1 PTH. CONCLUSIONS: Day 1 PTH is equivalent to (if not better than) drop in PTH in predicting short- and long-term PoSH. Preoperative PTH measurements may not be needed in the detection and/or management of PoSH after thyroid surgery.


Asunto(s)
Hipocalcemia , Hipoparatiroidismo , Hormona Paratiroidea , Complicaciones Posoperatorias , Tiroidectomía , Humanos , Hipoparatiroidismo/etiología , Hipoparatiroidismo/sangre , Hipoparatiroidismo/diagnóstico , Hormona Paratiroidea/sangre , Femenino , Tiroidectomía/efectos adversos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Hipocalcemia/etiología , Hipocalcemia/diagnóstico , Hipocalcemia/sangre , Adulto , Estudios Retrospectivos , Anciano , Periodo Posoperatorio , Curva ROC , Disección del Cuello/efectos adversos , Valor Predictivo de las Pruebas , Periodo Perioperatorio
2.
Surgeon ; 17(2): 102-106, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30170914

RESUMEN

INTRODUCTION: Recurrent laryngeal nerve (RLN) palsy is a potential complication of parathyroid surgery with significant morbidity and a cause of medico-legal litigation. Peri-operative laryngoscopy to assess RLN function helps identify a vocal cord palsy and guide management. The value of its routine use in asymptomatic patients is however unclear. The low risk of permanent palsy, rarity of true asymptomatic palsy and costs, discomfort and inconvenience to patients are arguments against routine laryngoscopy. This study assessed the results of routine laryngoscopy in patients having parathyroid surgery for primary hyperparathyroidism (PHPT). METHODS: All patients having parathyroid surgery for PHPT (exclusion: re-do surgery and concurrent thyroidectomy) over a 3-year period were included from a tertiary endocrine surgical unit. Data on voice-related outcomes and pre- and post-operative laryngoscopy, including its local cost, were collected and analysed. RESULTS: Of 189 patients who underwent parathyroid surgery, 66 had a unilateral neck exploration. The incidence of vocal cord palsy was 0.5% (1 in 186 patients) and 1.7% (3 in 179 patients) for pre- and post-operative laryngoscopy respectively. The single patient with pre-operative cord palsy was asymptomatic. Of the three with post-operative cord palsy, two were temporary and symptomatic and one was asymptomatic. In the region, the clinical commissioning group was charged £127.00 per laryngoscopy, amounting to £46,736.00 for the whole cohort. CONCLUSIONS: The rare nature of vocal cord palsy suggests laryngoscopy is not necessary for patients having surgery for PHPT. It may be reserved for patients with voice change and those having re-operative or concomitant thyroid surgery.


Asunto(s)
Hiperparatiroidismo Primario/cirugía , Laringoscopía , Paratiroidectomía , Cuidados Preoperatorios , Parálisis de los Pliegues Vocales/diagnóstico , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Masculino , Estudios Retrospectivos
3.
Ann R Coll Surg Engl ; 100(2): 135-139, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29182003

RESUMEN

Introduction The management of post-thyroidectomy hypocalcaemia should facilitate early discharge, and reduce risks of hypocalcaemia, readmission and treatment related hypercalcaemia. This paper describes the implementation, evaluation and revision a protocol for the optimal management of this condition. Methods Day 1 parathyroid hormone (PTH) measurements in addition to calcium measurements were commenced following review of the unit's outcomes and literature on post-thyroidectomy hypocalcaemia. Outcomes from a three-year cohort of patients undergoing thyroid surgery helped amend this protocol (revision 1) to reduce biochemical tests, stipulate the need, nature and dose of vitamin D/calcium supplements, and encourage early discharge. This was further validated over seven months to assess compliance, episodes of hyper and/or hypocalcaemia after discharge, readmissions and need for treatment changes. Further revisions were made (revision 2) and implemented. Results The temporary and long-term postoperative hypocalcaemia rates were 29.1% and 3.2% respectively. Repeat calcium measurements on the first day altered management in only 1.4% of cases. The revised protocol was adhered to in 90% of cases. One patient had hypocalcaemia (due to non-compliance) and one had hypercalcaemia. Revision 2 involved reducing the dose of calcium. Conclusions This is a good example of a unit protocol for post-thyroidectomy hypocalcaemia being developed and modified on the basis of the literature and local experience. Day 1 PTH and calcium levels determine the need for treatment and frequency of follow-up visits, facilitate early discharge, reduce risk of over and/or undertreatment, and are good indicators of permanent hypocalcaemia.


Asunto(s)
Hipocalcemia , Complicaciones Posoperatorias , Tiroidectomía/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hipocalcemia/diagnóstico , Hipocalcemia/tratamiento farmacológico , Hipocalcemia/epidemiología , Hipocalcemia/prevención & control , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Adulto Joven
4.
Nanotechnology ; 28(40): 405204, 2017 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-28787278

RESUMEN

In this paper, we study band-to-band and intersubband (ISB) characteristics of Si- and Ge-doped GaN/AlN heterostructures (planar and nanowires) structurally designed to absorb in the short-wavelength infrared region, particularly at 1.55 µm. Regarding the band-to-band properties, we discuss the variation of the screening of the internal electric field by free carriers, as a function of the doping density and well/nanodisk size. We observe that nanowire heterostructures consistently present longer photoluminescence decay times than their planar counterparts, which supports the existence of an in-plane piezoelectric field associated to the shear component of the strain tensor in the nanowire geometry. Regarding the ISB characteristics, we report absorption covering 1.45-1.75 µm using Ge-doped quantum wells, with comparable performance to Si-doped planar heterostructures. We also report similar ISB absorption in Si- and Ge-doped nanowire heterostructures indicating that the choice of dopant is not an intrinsic barrier for observing ISB phenomena. The spectral shift of the ISB absorption as a function of the doping concentration due to many body effects confirms that Si and Ge efficiently dope GaN/AlN nanowire heterostructures.

5.
Nanotechnology ; 27(14): 145201, 2016 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-26902654

RESUMEN

This paper assesses the effects of Si doping on the properties of nonpolar m-plane GaN/AlGaN quantum wells (QWs) designed for intersubband (ISB) absorption in the far-infrared spectral range. For doping levels up to 3 × 10(12) cm(-2), structural analysis reveals uniform QWs with abrupt interfaces and no epitaxially induced defects. Cathodoluminescence spectroscopy confirms the homogeneity of the multiple QWs along the growth direction. Increasing the doping density in the QWs from 1 × 10(11) cm(-2) to 3 × 10(12) cm(-2) induces a broadening of the photoluminescence as well as a reduction of the exciton localization energy in the alloy. Also, enhancement of the ISB absorption is observed, along with a blue shift and widening of the absorption peak. The magnitude of the ISB absorption saturates for doping levels around 1 × 10(12) cm(-2), and the blue shift and broadening increase less than theoretically predicted for the samples with higher doping levels. This is explained by the presence of free carriers in the excited electron level due to the increase of the Fermi level energy.

6.
Nanotechnology ; 26(43): 435201, 2015 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-26437371

RESUMEN

This paper assesses intersubband (ISB) transitions in the 1-10 THz frequency range in nonpolar m-plane GaN/AlGaN multi-quantum-wells deposited on free-standing semi-insulating GaN substrates. The quantum wells (QWs) were designed to contain two confined electronic levels, decoupled from the neighboring wells. Structural analysis reveals flat and regular QWs in the two perpendicular in-plane directions, with high-angle annular dark-field scanning transmission electron microscopy images showing inhomogeneities of the Al composition in the barriers along the growth axis. We do not observe extended structural defects (stacking faults or dislocations) introduced by the epitaxial process. Low-temperature ISB absorption from 1.5 to 9 THz (6.3-37.4 meV) is demonstrated, covering most of the 7-10 THz band forbidden to GaAs-based technologies.

7.
Case Rep Surg ; 2014: 454502, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25478281

RESUMEN

Purpose. Tailgut cysts with malignant transformation are rare entities. We discuss the diagnostic strategy and treatment of a malignancy within a tailgut cyst. Methods. In this study we report on the case of a 61-year-old man with a malignant neuroendocrine tumour arising within a tailgut cyst and an overview of the literature emphasising the histopathological characteristics and differential diagnosis. Results. Our patient presented with lower back pain, rectal pain, and increased urgency of defecation. MRI scan and CT-guided biopsy on histological analysis revealed a diagnosis of carcinoid tumour of the presacral space. The patient subsequently underwent an abdominoperineal excision of the rectum. Conclusions. This case highlights the importance of tailgut cysts as a differential diagnosis of presacral masses. It is a rare congenital lesion developing from remnants of the embryonic postanal gut and is predominantly benign in nature. Approximately half of cases remain asymptomatic; therefore, diagnosis is often delayed. Magnetic resonance imaging is the investigation of choice and an awareness of the possibility of malignant potential is critical to avoiding missed diagnosis and subsequent morbidity. Complete surgical excision allows accurate diagnosis, confirmation of oncological clearance, and prevention of mortality.

8.
J Sport Exerc Psychol ; 32(3): 324-38, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20587821

RESUMEN

The purpose of the current study was to examine the influence of perceived motivational climate on achievement goals in physical education using a structural equation mixture modeling (SEMM) analysis. Within one analysis, we identified groups of students with homogenous profiles in perceptions of motivational climate and examined the relationships between motivational climate, 2 x 2 achievement goals, and affect, concurrently. The findings of the current study showed that there were at least two distinct groups of students with differing perceptions of motivational climate: one group of students had much higher perceptions in both climates compared with the other group. Regardless of their grouping, the relationships between motivational climate, achievement goals, and enjoyment seemed to be invariant. Mastery climate predicted the adoption of mastery-approach and mastery-avoidance goals; performance climate was related to performance-approach and performance-avoidance goals. Mastery-approach goal had a strong positive effect while performance-avoidance had a small negative effect on enjoyment. Overall, it was concluded that only perception of a mastery motivational climate in physical education may foster intrinsic interest in physical education through adoption of mastery-approach goals.


Asunto(s)
Logro , Objetivos , Modelos Psicológicos , Motivación , Educación y Entrenamiento Físico , Percepción Social , Adolescente , Rendimiento Atlético , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
9.
Br J Surg ; 95(8): 1044-50, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18563788

RESUMEN

BACKGROUND: Staples are made of titanium, which elicits minimal tissue reaction. The authors have encountered foreign body reaction associated with stapled human gastrointestinal anastomoses, although the literature has no reports of this. The aim of this study was to identify the refractile foreign materials causing this reaction. METHODS: Histological sections were taken from 14 gastrointestinal specimens from patients with a history of a stapled anastomosis within the specimen excised. These were reviewed by light and polarization microscopy. Scanning electron microscopy and energy dispersive X-ray analysis were carried out on these sections, staples and stapler cartridges used for gastrointestinal surgery. RESULTS: Foreign bodies rich in fluorine were found in three patients, and those rich in carbon in 12. Other elements identified included oxygen, calcium, sodium, potassium, magnesium, aluminium and silicon. One specimen was found to contain titanium with no surrounding foreign body reaction. Stapler cartridges contained carbon, oxygen, fluorine, calcium, sodium, potassium, magnesium, aluminium, silicon and traces of titanium. Staples were composed of pure titanium with some fibrous material on the surface containing elements found in stapler cartridges. CONCLUSION: The presence of foreign body reaction was confirmed in stapled human gastrointestinal anastomoses. The source of refractile materials eliciting this reaction was the stapler cartridges.


Asunto(s)
Reacción a Cuerpo Extraño/etiología , Grapado Quirúrgico/efectos adversos , Suturas/efectos adversos , Titanio , Anastomosis Quirúrgica , Humanos , Microscopía Electrónica de Rastreo , Grapado Quirúrgico/instrumentación
10.
Oncogene ; 27(1): 1-8, 2008 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-17603560

RESUMEN

Although Kruppel-like factor 5 (KLF5) is a transcription factor that has been implicated in pathways critical to carcinogenesis, controversy persists as to whether it functions as a tumor suppressor or as an oncogene. Here, we describe a novel role for KLF5 in a p53-independent apoptotic pathway. Using RNA-interference technology, we show that cells deficient in KLF5 have increased sensitivity to DNA damage, regardless of p53 status. Both p53 and p53-dependent factors are unaffected by KLF5 depletion. Instead, the apoptotic phenotype consequent to damage is associated with reduced bad phosphorylation, and downregulation of Pim1. Consistently, transfection of wild-type Pim1 is sufficient to rescue this phenotype. Previous data have shown a number of putative Sp1-binding consensus sequences on the Pim1 promoter. Remarkably, chromatin immunoprecipitation studies show that KLF5 binds to the Pim1 promoter, and that binding increases soon after damage. These results identify a novel, p53-independent apoptotic pathway through which KLF5 functions in response to DNA damage. Therapeutic deregulation of this pathway could be used to modulate chemosensitivity.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/fisiología , Apoptosis/fisiología , Factores de Transcripción de Tipo Kruppel/fisiología , Proteínas Proto-Oncogénicas c-pim-1/fisiología , Proteína p53 Supresora de Tumor/fisiología , Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/deficiencia , Proteínas Reguladoras de la Apoptosis/genética , Supervivencia Celular/genética , Supervivencia Celular/fisiología , Daño del ADN/genética , Células HCT116 , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Fosforilación , Unión Proteica/genética , Proteínas Proto-Oncogénicas c-pim-1/biosíntesis , Proteínas Proto-Oncogénicas c-pim-1/genética , Transducción de Señal/genética , Transfección , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética , Proteína Letal Asociada a bcl/metabolismo
12.
Br J Nurs ; 15(5): 282-4, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16607259

RESUMEN

This article aims to assess whether a detachable functional focused rigidity cast can be used as a one-off definitive treatment for proximal 5th metatarsal fractures. A prospective trial was carried out over a 2-year period. Forty-one patients with proximal 5th metatarsal fractures (tuberosity and Jones) were recruited and treated with a detachable focused rigidity cast after appropriate consent. Of the 39 patients with follow-up, six had a Jones fracture and 33 had tuberosity fractures. All 33 patients with tuberosity fractures achieved clinical union within 4-5 weeks (mean of 4.2 weeks). Four of the six patients with Jones fractures achieved clinical union in 8-12 weeks. One achieved union in 14 weeks and one underwent open reduction and internal fixation for delayed union. There were no complications related to the cast. The results support the use of a detachable focused rigidity cast as a one-off definitive treatment of tuberosity fractures of the 5th metatarsal. However, all the Jones fractures and the diaphyseal fractures should be referred to an orthopaedic team for further management.


Asunto(s)
Moldes Quirúrgicos/normas , Fracturas Óseas/terapia , Huesos Metatarsianos/lesiones , Adhesivos , Actitud Frente a la Salud , Ensayos Clínicos como Asunto , Diseño de Equipo , Femenino , Fijación Interna de Fracturas , Curación de Fractura , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/psicología , Fracturas no Consolidadas/etiología , Fracturas no Consolidadas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Evaluación en Enfermería , Estudios Prospectivos , Radiografía , Encuestas y Cuestionarios , Resultado del Tratamiento
13.
Anaesthesia ; 58(8): 740-4, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12859464

RESUMEN

Twenty-four gynaecological patients receiving postoperative patient-controlled analgesia were enrolled in an open cross-over pilot study evaluating two new formulations of nasal fentanyl spray. The primary outcome was the bioavailability of nasal fentanyl in comparison with intravenous fentanyl. This manuscript describes the clinical outcomes of quality of postoperative analgesia and patient acceptability. There were 21 complete data sets for both sequences of the cross-over design. In randomised order, patients received approximately 50 microg of fentanyl in a single dose by intranasal and intravenous administration, but separated by at least 2 h. Analgesia was of rapid onset (within 5 min) and similar quality. There was no significant difference in side-effects. Four patients experienced mild nasal stinging and although 10 (42%) preferred intravenous administration, seven (29%) preferred intranasal and six (25%) had no preference. We conclude that these formulations of fentanyl, delivered as nasal spray, have potential clinical utility.


Asunto(s)
Analgésicos Opioides/administración & dosificación , Fentanilo/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Administración Intranasal , Adulto , Analgesia Controlada por el Paciente/métodos , Analgésicos Opioides/sangre , Analgésicos Opioides/química , Disponibilidad Biológica , Química Farmacéutica , Estudios Cruzados , Femenino , Fentanilo/sangre , Fentanilo/química , Humanos , Inyecciones Intravenosas , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/sangre , Satisfacción del Paciente , Proyectos Piloto
14.
Med J Malaysia ; 58(5): 641-6, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15190647

RESUMEN

We retrospectively studied the records of 6 Malaysian children who were diagnosed with Alagille Syndrome (AGS) according to this criteria from January 1999 to January 2001, at the Institute of Paediatrics, Kuala Lumpur Hospital. Four patients (66%) had a positive family history. Thirteen individuals (6 patients and 7 relatives) were diagnosed with AGS in these 5 families. Only 6/13 (46%) of them presented with liver involvement. All 6 patients presented with typical facies and cholestasis (100%). Three (50%) presented with portal hypertension (PHT) with synthetic liver dysfunction (1 died), 1/6 (17%) have PHT and normal synthetic liver function. Two have cleared their jaundice but have biochemical evidence of hepatitis and hepatomegaly, four have congenital heart disease 5/6 posterior embryotoxon, 2/6 butterfly vertebrae, 4/6 hyperlipidaemia and 4/6 failure to thrive. One patient has a Jagged-1 gene disruption at the translocation breakpoint locus 20p12.3 2n = 46,XX,t(12.20) (q22, p12.3). 5/6 (83%) are still alive. Two-thirds of our patients developed chronic liver disease by 3 years of age. Two-thirds of the index patients have a family history. Only 46% of individuals in these families have clinical evidence of liver involvement. Mortality depends on cardiac/renal disease, end-stage liver failure and intercurrent infection.


Asunto(s)
Síndrome de Alagille/fisiopatología , Síndrome de Alagille/complicaciones , Síndrome de Alagille/genética , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Malasia , Masculino
15.
J Comp Physiol B ; 171(5): 357-67, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11497123

RESUMEN

Bostrichthys sinensis inhabits brackish water, living in the crevices of the river mouths of Shang Xi and Guangdong, China. In its natural habitat, it may encounter aerial exposure frequently during low tides, and it usually remains quiescent in the absence of water. Upon aerial exposure in the laboratory, the ammonia excretion rate decreased to one-fourth that of the submerged control. Although all the enzymes of the ornithine-urea cycle were detected in the liver of this fish, the activity of hepatic carbamoyl phosphate synthetase was too low for the cycle to be functioning. Indeed, ammonia accumulated in the tissues and was not converted to urea. Results indicate that ammonia produced through amino acid catabolism was detoxified to glutamine during the first 24 h of aerial exposure. The excess amount of glutamine stored in the muscle during this period couldaccount approximately for the reduction in ammonia equivalent excreted. There was indeed a significant increase in the activity of glutamine synthetase from the liver of specimens exposed to terrestrial conditions. In contrast to the production of alanine, formation of glutamine is energetically expensive. Since B. sinensis remained relatively inactive on land, the reduction in energy demand for muscular activity might provide it with the opportunity to exploit glutamine formation as a means to detoxify ammonia. After 72 h of aerial exposure, B. sinensis reduced internal ammonia production, possibly through reductions in proteolysis and amino acid catabolism, to avoid excessive accumulation of ammonia.


Asunto(s)
Adaptación Fisiológica/fisiología , Amoníaco/metabolismo , Peces/metabolismo , Glutamina/metabolismo , Aire , Aminoácidos/metabolismo , Animales , Metabolismo Energético/fisiología , Glutamato-Amoníaco Ligasa/metabolismo , Hígado/enzimología , Músculo Esquelético/metabolismo , Urea/metabolismo
16.
J Synchrotron Radiat ; 8(Pt 2): 360-2, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512780

RESUMEN

A new laboratory spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) has been developed. This spectrometer is suitable for measurements of X-ray Absorption Fine Structure (XAFS) spectrum in surface sensitive fluorescence and electron emission detection modes as well as in standard transmission mode. It is the advantage of this spectrometer that a wide range of x-ray energy scanning between 0.48 and 41 keV is available. At the Cu K-edge, a energy resolution of about 2 eV has been achieved. The spectrometer has been used to analyze the Al2O3 (40 A and 500 A)/Si(100) with total electron yield measurement.

17.
J Exp Biol ; 204(Pt 9): 1605-14, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11398749

RESUMEN

This study was designed to elucidate the strategies adopted by mudskippers to handle endogenous ammonia during aerial exposure in constant darkness. Under these conditions, specimens exhibited minimal locomotory activity, and the ammonia and urea excretion rates in both Periophthalmodon schlosseri and Boleophthalmus boddaerti decreased significantly. As a consequence, ammonia accumulation occurred in the tissues of both species of mudskipper. A significant increase in urea levels was found in the liver of P. schlosseri after 24h of aerial exposure, but no similar increase was seen in the tissues of B. boddaerti. It is unlikely that these two species of mudskipper detoxified ammonia to urea during aerial exposure since B. boddaerti does not possess a complete ornithine-urea cycle (OUC) and, although all the OUC enzymes were present in P. schlosseri, the activity of carbamoyl phosphate synthetase present in the liver mitochondria was too low to render the OUC functional for ammonia detoxification. Peritoneal injection of 15NH4Cl into P. schlosseri showed that this mudskipper was capable of incorporating some of the labelled ammonia into urea in its liver. However, aerial exposure did not affect this capability and did not induce detoxification of the accumulated ammonia to urea. Mudskippers exposed to terrestrial conditions and constant darkness did, however, show significant decreases in the total free amino acid content in the liver and blood, in the case of P. schlosseri and in the muscle of B. boddaerti. No changes in the alanine or glutamine content of the muscle were found in either species. Analyses of the balance between the reduction in nitrogenous excretion and the increase in nitrogenous accumulation further revealed that these two species of mudskipper were capable of reducing their protein and amino acid catabolic rates. Such adaptations constitute the most efficient way to avoid the build-up of internal ammonia, and would render unnecessary the detoxification of ammonia through energetically expensive pathways. This finding may be the first report of a teleost fish showing a reduction in proteolysis and amino acid catabolism in response to aerial exposure.


Asunto(s)
Aire , Aminoácidos/metabolismo , Amoníaco/metabolismo , Oscuridad , Perciformes/metabolismo , Proteínas/metabolismo , Alanina/metabolismo , Aminoácidos/sangre , Cloruro de Amonio/administración & dosificación , Cloruro de Amonio/metabolismo , Animales , Carbamoil-Fosfato Sintasa (Amoniaco)/metabolismo , Carbamoil-Fosfato Sintasa (Glutamina-Hidrolizante)/metabolismo , Glutamina/metabolismo , Inactivación Metabólica , Cinética , Hígado/metabolismo , Mitocondrias Hepáticas/enzimología , Actividad Motora , Músculos/metabolismo , Urea/metabolismo
18.
Med J Malaysia ; 56(4): 414-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12014759

RESUMEN

A total of 97 children aged 1 month to 16 years (mean 6.6 years) had upper endoscopies performed in Paediatric Institute, Kuala Lumpur Hospital between January 1997 and December 1999 for various gastrointestinal symptoms. Of these 70 children were tested for Helicobacter pylori. The four most common indications for upper endoscopy were recurrent abdominal pain, upper gastrointestinal bleeding, epigastric pain and vomiting. The overall prevalence of this infection in this heterogenous group of symptomatic children was 10% (7/70). This study shows that H.pylori positivity in a routine endoscopy population is low and does not appear to be associated with specific symptoms.


Asunto(s)
Abdomen/patología , Enfermedades Gastrointestinales/epidemiología , Enfermedades Gastrointestinales/etiología , Gastroscopía , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/aislamiento & purificación , Abdomen/microbiología , Adolescente , Niño , Preescolar , Femenino , Enfermedades Gastrointestinales/patología , Infecciones por Helicobacter/patología , Humanos , Lactante , Malasia/epidemiología , Masculino , Prevalencia
19.
Med J Malaysia ; 54(1): 120-4, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10972016

RESUMEN

We describe a 2 year-old non-immunocompromised girl with disseminated histoplasmosis who presented with a 2-month history of fever and bloody diarrhoea. On presentation, she was severely wasted and anaemic. There were gross hepatosplenomegaly and multiple lymphadenopathy. A septic screen was negative. A subsequent stool culture isolated Salmonella enteriditis. Serial Widal-Weil Felix (WWF) titres showed serological response after 2 weeks of Ceftriaxone. However, she continued to have spiking fever, bloody diarrhoea and weight loss. She developed pancytopaenia and disseminated intravascular coagulation. A bone marrow aspirate and trephine, and lymph node biopsy showed the presence of Histoplasma capsulatum, confirmed by Gomori-Methenamine Silver staining. She responded to intravenous amphotericin B followed by fluconazole (intravenous then oral) for 6 months after discharge. Human Immunodeficiency Virus screening tests were negative. Complement and immunoglobulin levels were normal. T and B enumeration tests showed gross leucopaenia with very low T cell function with defective phagocytic function. A repeat T and B cell enumeration test and phagocytic function tests done 3 months later were normal.


Asunto(s)
Histoplasmosis/inmunología , Sistema Inmunológico/fisiopatología , Anfotericina B/uso terapéutico , Antibacterianos/uso terapéutico , Antifúngicos/uso terapéutico , Médula Ósea/microbiología , Preescolar , Coagulación Intravascular Diseminada/microbiología , Femenino , Fluconazol/uso terapéutico , Histoplasma/aislamiento & purificación , Histoplasmosis/complicaciones , Histoplasmosis/tratamiento farmacológico , Histoplasmosis/microbiología , Humanos , Pancitopenia/microbiología
20.
Artículo en Inglés | MEDLINE | ID: mdl-9827062

RESUMEN

The concentrations of ammonia in the plasma of the mudskipper Boleophthalmus boddaerti exposed to cyanide for 1-6 days were significantly greater than the respective values of the controls. This was due to an increase in the production of NH3 in the muscle and an increase in the retention of NH3 and/or NH4+ in the blood of the cyanide-exposed fish when compared to controls. Cyanide exposure significantly increased the specific activity of muscle AMP deaminase. Since adenylosuccinate synthetase and lyase were also present in the muscle, exposure to cyanide might increase the production of NH3 from the catabolism of purine nucleotides. B. boddaerti exposed to cyanide excreted significantly less ammonia than the control fish. Results indicate changes in the permeability of the epithelial surfaces of the cyanide-exposed fish to NH3 and/or NH4+. Since the tissues and organs needed time to activate the inducible cyanide detoxification mechanisms, the increase in the production of NH3 might be an important defensive mechanism for B. boddaerti during the early phase of cyanide exposure.


Asunto(s)
Amoníaco/sangre , Peces/metabolismo , Cianuro de Hidrógeno/toxicidad , AMP Desaminasa/análisis , Adenilosuccinato Sintasa/análisis , Animales , Femenino , Peces/sangre , Branquias/metabolismo , Concentración de Iones de Hidrógeno , Masculino , Músculos/metabolismo , Singapur
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