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1.
Crit Rev Toxicol ; 49(8): 637-669, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-32009535

RESUMEN

Corrosive chemical substance ingestions are a major problem, especially in developing countries, but also in developed countries such as the United States, France, and Belgium. Ingestions may be deliberate as suicide attempts (mostly in adolescents and adults) or accidental (mostly in children). The results can be devastating in terms of individual suffering and disability, but also in terms of resource utilization and costs. In developing countries, outcomes may be worse because of limited medical/surgical resources. Common sequelae include gastrointestinal (GI) tract (esophagus, stomach, pylorus, and duodenum) stricture formation, GI tract perforation, and hemorrhage. Systemic effects may also occur, such as disseminated intravascular coagulation (DIC), multi-organ system failure, and sepsis. Various interventions in the acute phase to reduce the severity of injury have been attempted, but there are no large controlled clinical trials to demonstrate efficacy. Dilation therapy in various forms is commonly used for the treatment of strictures and a variety of surgical procedures including esophagectomy and delayed replacement may be required in severe corrosive injury cases.


Asunto(s)
Quemaduras Químicas , Cáusticos/envenenamiento , Tracto Gastrointestinal , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Intento de Suicidio
2.
Eur Arch Otorhinolaryngol ; 274(1): 175-179, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27376644

RESUMEN

Joseph Gensoul was a pioneer of ENT surgery. In 1827, he performed the first total maxillectomy on 17-year-old boy. His work inspired many surgeons, who were previously unwilling to remove maxillary tumours. A paleopathological study performed in the Dupuytren museum allowed us to identify a skull from the early 19th century, with a large maxillar tumour. There were indications that this skull was operated according to Gensoul's technique. The aim of this study is to confirm that this patient had, in fact, received this surgical treatment. This is a historical and descriptive paleopathological study of a skull of the early 19th century of Dupuytren Museum in Paris. The historical research was conducted in collaboration with the French Academy of Medicine and the Museum of Medicine History (Paris). Bones mark cut studies allowed us to confirm that the patient was operated according to the method described by Gensoul in his "Surgical letter" in 1833. Our historical research has allowed us to understand the perspectives of surgeons in the 19th century and the intellectual processes that led to this discovery. At a time when the robotization and industrialization dominate our art, it is interesting to look to our past, our origins, and our history. The study of ancient humans remains and allows us to understand the origin of our specialty and pay tribute to these pioneering surgeons. Their intellectual approach and boldness should be acknowledged and applauded, especially as it is also the key to our success.


Asunto(s)
Otolaringología/historia , Procedimientos Quirúrgicos Otorrinolaringológicos/historia , Historia del Siglo XIX , Humanos , Maxilar/cirugía , Neoplasias Maxilares/cirugía , Museos , Paris , Cráneo
3.
Pediatr Int ; 55(2): e29-31, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23679180

RESUMEN

Osteoid osteoma is a solitary, benign lesion of bone causing significant nocturnal pain. Magnetic resonance imaging (MRI), computed tomography (CT), and bone scan are commonly used in this diagnosis. A case of osteoid osteoma of the distal femur mimicking chronic osteomyelitis with Brodie's abscess is reported and discussed. Initial radiographs and MRI showed a lesion of the distal femur consistent with subacute osteomyelitis with a Brodie's abscess. Because primary malignant tumor could not be eliminated, surgical biopsy was carried out. Histological examination showed a typical nidus consistent with the diagnosis of osteoid osteoma. Subacute osteomyelitis (Brodie's abscess) may be difficult to distinguish from other malignant or benign bone lesions as osteoid osteoma. CT usually is recommended as the best imaging procedure to identify the nidus and confirm the diagnosis. MRI also can be used for this purpose. Surgical biopsy remains mandatory for unclear lesions before deciding on appropriate treatment.


Asunto(s)
Absceso/diagnóstico , Neoplasias Óseas/diagnóstico , Fémur , Osteoma Osteoide/diagnóstico , Osteomielitis/diagnóstico , Adolescente , Biopsia , Neoplasias Óseas/cirugía , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Osteoma Osteoide/cirugía , Tomografía Computarizada por Rayos X
4.
J Pediatr Gastroenterol Nutr ; 52(6): 734-9, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21478758

RESUMEN

BACKGROUND AND OBJECTIVE: Tufting enteropathy (TE) is a congenital abnormality of intestinal mucosa development characterized by severe intestinal failure requiring parenteral nutrition (PN) and, in some cases, small bowel transplantation. A few patients have had a more favorable outcome. The objective of this study was to evaluate possible correlations between histological lesion severity in duodenal biopsies and clinical outcomes in children with TE. PATIENTS AND METHODS: We retrospectively reviewed the records of patients diagnosed with TE between 1993 and 2003 at our institution based on intractable neonatal-onset diarrhea with prolonged dependence on PN and duodenal biopsy findings of villous atrophy, epithelial dysplasia with enterocyte dedifferentiation and disorganization (tufting) of the surface epithelium, and crypt abnormalities. The histological lesions were assessed semiquantitatively and compared with the clinical outcomes including dependence on PN. RESULTS: Seven children, all from consanguineous parents, were studied for a median of 6.5 years. Three were permanently weaned off PN and experienced normal growth without nutritional assistance. Initial biopsies in all 3 children showed severe diffuse histological lesions. At weaning off PN, 2 of these 3 patients had persistent, although less diffuse, histological lesions. CONCLUSIONS: Progressive weaning off PN is possible in some children with TE. In our experience, this favorable outcome was not predicted by histological lesion severity, although the lesions improved in some patients. New biomarkers for identifying the histological lesions and predicting the outcome would be useful.


Asunto(s)
Diarrea/terapia , Duodeno/patología , Enfermedades Intestinales/terapia , Mucosa Intestinal/anomalías , Mucosa Intestinal/patología , Nutrición Parenteral , Diarrea/etiología , Femenino , Humanos , Lactante , Recién Nacido , Enfermedades Intestinales/complicaciones , Enfermedades Intestinales/patología , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
5.
PLoS Med ; 4(8): e253, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17696642

RESUMEN

BACKGROUND: Langerhans cell histiocytosis (LCH) is a rare clonal granulomatous disease that affects mainly children. LCH can involve various tissues such as bone, skin, lung, bone marrow, lymph nodes, and the central nervous system, and is frequently responsible for functional sequelae. The pathophysiology of LCH is unclear, but the uncontrolled proliferation of Langerhans cells (LCs) is believed to be the primary event in the formation of granulomas. The present study was designed to further investigate the nature of proliferating cells and the immune mechanisms involved in the LCH granulomas. METHODS AND FINDINGS: Biopsies (n = 24) and/or blood samples (n = 25) from 40 patients aged 0.25 to 13 y (mean 7.8 y), were studied to identify cells that proliferate in blood and granulomas. We found that the proliferating index of LCs was low ( approximately 1.9%), and we did not observe expansion of a monocyte or dendritic cell compartment in patients. We found that LCH lesions were a site of active inflammation, tissue remodeling, and neo-angiogenesis, and the majority of proliferating cells were endothelial cells, fibroblasts, and polyclonal T lymphocytes. Within granulomas, interleukin 10 was abundant, LCs expressed the TNF receptor family member RANK, and CD4(+) CD25(high) FoxP3(high) regulatory T cells (T-regs) represented 20% of T cells, and were found in close contact with LCs. FoxP3(+) T-regs were also expanded compared to controls, in the blood of LCH patients with active disease, among whom seven out of seven tested exhibited an impaired skin delayed-type hypersensitivity response. In contrast, the number of blood T-regs were normal after remission of LCH. CONCLUSIONS: These findings indicate that LC accumulation in LCH results from survival rather than uncontrolled proliferation, and is associated with the expansion of T-regs. These data suggest that LCs may be involved in the expansion of T-regs in vivo, resulting in the failure of the host immune system to eliminate LCH cells. Thus T-regs could be a therapeutic target in LCH.


Asunto(s)
Histiocitosis de Células de Langerhans/inmunología , Hipersensibilidad Tardía , Células de Langerhans/fisiología , Linfocitos T Reguladores/fisiología , Adolescente , Proliferación Celular , Niño , Preescolar , Humanos , Lactante , Células de Langerhans/inmunología , Linfocitos T Reguladores/inmunología
6.
Toxins (Basel) ; 9(8)2017 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-28783135

RESUMEN

Bothrops lanceolatus, commonly named 'Fer-de-Lance', is an endemic snake of the French Caribbean Island of Martinique. Envenomations by B. lanceolatus present clinical aspects characterized by systemic thrombotic syndrome and important local inflammation, involving edema and pain but limited hemorrhage. To investigate mechanisms of venom-induced inflammation, B. lanceolatus venom was characterized, its cross-reactivity with bothropic antivenom explored, its cytotoxicity on human keratinocytes and vascular cells, and the production of cytokines and chemokines were analyzed. We used electrophoretic separation, zymography, colorimetric or fluorimetric enzymatic assays, and immunochemical assays. Therapeutic South American bothropic antivenom cross-reacted with B. lanceolatus venom and completely or partially abolished its PLA2, hyaluronidase, and proteolytic activities, as well as its cytotoxicity for keratinocytes. The substrate specificity of B. lanceolatus venom proteases was emphasized. B. lanceolatus venom cytotoxicity was compared to the B. jararaca venom. Both venoms were highly cytotoxic for keratinocytes (HaCaT), whereas B. lanceolatus venom showed particularly low toxicity for endothelial cells (EAhy926). Patterns of cytokine and chemokine production by cells exposed to the venoms were highly pro-inflammatory. Thus, the results presented here show that B. lanceolatus venom toxins share important antigenic similarities with South American Bothrops species toxins, although their proteases have acquired particular substrate specificity. Moreover, the venom displays important cytotoxic and pro-inflammatory action on human cell types such as keratinocytes and endothelial cells, which are important players in the local and systemic compartments affected by the envenomation.


Asunto(s)
Bothrops , Venenos de Crotálidos/toxicidad , Animales , Antivenenos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Hialuronoglucosaminidasa/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Fosfolipasas/metabolismo , Proteolisis , Mordeduras de Serpientes , Tromboplastina/metabolismo
7.
Orphanet J Rare Dis ; 11(1): 52, 2016 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-27129381

RESUMEN

Infantile-onset multisystem neurologic, endocrine, and pancreatic disease (IMNEPD) has been recently linked to biallelic mutation of the peptidyl-tRNA hydrolase 2 gene PTRH2. Two index patients with IMNEPD in the original report had multiple neurological symptoms such as postnatal microcephaly, intellectual disability, developmental delay, sensorineural deafness, cerebellar atrophy, ataxia, and peripheral neuropathy. In addition, distal muscle weakness and abnormalities of thyroid, pancreas, and liver were found. Here, we report five further IMNEPD patients with a different homozygous PTRH2 mutation, broaden the phenotypic spectrum of the disease and differentiate common symptoms and interindividual variability in IMNEPD associated with a unique mutation. We thereby hope to better define IMNEPD and promote recognition and diagnosis of this novel disease entity.


Asunto(s)
Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Regulación Enzimológica de la Expresión Génica , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Enfermedades Pancreáticas/genética , Enfermedades Pancreáticas/patología , Humanos , Mutación , Linaje
8.
Burns ; 31(2): 205-11, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15683694

RESUMEN

PRECIS: During the 4 years of this study, we noted 66 cases of alkali ocular burns, or approximately 16 cases per year, nearly half (45.5%) of which are due to an assault. For grade 1 and 2 burns the time elapsed to reepithelialization appears to be shorter when rinsed with Diphoterine* versus physiological solution. PURPOSE: Comparison of the effectiveness of two rinsing solutions for emergency use: a physiological solution and an amphoteric solution (Diphoterine*, Laboratories Prevor, Valmondois, France). Description of the clinical and progressive characteristics of alkali burns treated at the University Hospital Center of Fort de France in Martinique (French West Indies). DESIGN: Prospective consecutive observational case series and nonrandomized comparative study. PARTICIPANTS: Sixty-six patients were included. The total number of burned eyes is 104. Forty-eight eyes (46%) were rinsed with physiological solution and 56 eyes (54%) with Diphoterine*. METHODS: All patients benefited from an ocular rinse with 500ml of physiological solution or Diphoterine*, followed by a complete ophthalmologic exam. The ocular injuries were classified according to the Roper-Hall modification of the Hughes classification system. The same standardized therapeutic protocol was applied and adapted to the seriousness of the burn. MAIN OUTCOME MEASURES: Demographic data, time to corneal reepithelialization, final best corrected visual acuity and complications were analysed. RESULTS: Twenty-eight (42.4%) patients have a unilateral burn and 38 (57.6%) patients have bilateral burns. In decreasing order of frequency, the circumstances surrounding the injury are: assaults in 45.5% of cases (n=30), work-related accidents in 32% of cases (n=31), and domestic accidents in 23% of cases (n=15). For grade 1 and 2 burns the time elapsed to reepithelialization appears to be shorter when rinsed with Diphoterine* versus physiological solution (respectively): 1.9+/-1 days versus 11.1+/-1.4 days (p=10(-7)) and 5.6+/-4.9 days versus 10+/-9.2 days (p=0.02). For grade 3 and 4 burns, there are complications in 11 cases (11.6%): 8 corneal opacities and 3 perforations. CONCLUSIONS: This study is the first conducted in humans that takes into account the type of ocular rinse product used in the progressive follow-up study of injuries. The time elapsed to reepithelialization is shorter with Diphoterine* for grade 1 and 2 burns. There are not enough cases of grade 3 and 4 burns to make a conclusion. Diphoterine* seems very effective in terms of its mechanism of action and the experimental and clinical results.


Asunto(s)
Álcalis , Quemaduras Químicas/tratamiento farmacológico , Quemaduras Oculares/inducido químicamente , Soluciones Oftálmicas/uso terapéutico , Accidentes Domésticos , Accidentes de Trabajo , Adulto , Quemaduras Químicas/complicaciones , Quemaduras Químicas/fisiopatología , Quemaduras Oculares/complicaciones , Quemaduras Oculares/tratamiento farmacológico , Femenino , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/complicaciones , Enfermedades Profesionales/tratamiento farmacológico , Compuestos Orgánicos , Estudios Prospectivos , Resultado del Tratamiento , Violencia , Cicatrización de Heridas/fisiología
10.
Toxins ; 9(8): 244, 2017.
Artículo en Inglés | SES-SP, SES SP - Instituto Butantan, SES-SP | ID: but-ib15068

RESUMEN

Bothrops lanceolatus, commonly named 'Fer-de-Lance', is an endemic snake of the French Caribbean Island of Martinique. Envenomations by B. lanceolatus present clinical aspects characterized by systemic thrombotic syndrome and important local inflammation, involving edema and pain but limited hemorrhage. To investigate mechanisms of venom-induced inflammation, B. lanceolatus venom was characterized, its cross-reactivity with bothropic antivenom explored, its cytotoxicity on human keratinocytes and vascular cells, and the production of cytokines and chemokines were analyzed. We used electrophoretic separation, zymography, colorimetric or fluorimetric enzymatic assays, and immunochemical assays. Therapeutic South American bothropic antivenom cross-reacted with B. lanceolatus venom and completely or partially abolished its PLA2, hyaluronidase, and proteolytic activities, as well as its cytotoxicity for keratinocytes. The substrate specificity of B. lanceolatus venom proteases was emphasized. B. lanceolatus venom cytotoxicity was compared to the B. jararaca venom. Both venoms were highly cytotoxic for keratinocytes (HaCaT), whereas B. lanceolatus venom showed particularly low toxicity for endothelial cells (EAhy926). Patterns of cytokine and chemokine production by cells exposed to the venoms were highly pro-inflammatory. Thus, the results presented here show that B. lanceolatus venom toxins share important antigenic similarities with South American Bothrops species toxins, although their proteases have acquired particular substrate specificity. Moreover, the venom displays important cytotoxic and pro-inflammatory action on human cell types such as keratinocytes and endothelial cells, which are important players in the local and systemic compartments affected by the envenomation.

11.
PLoS One ; 6(7): e22080, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21779377

RESUMEN

Atelopus franciscus is a diurnal bufonid frog that lives in South-American tropical rain forests. As in many other frogs, males produce calls to defend their territories and attract females. However, this species is a so-called "earless" frog lacking an external tympanum and is thus anatomically deaf. Moreover, A. franciscus has no external vocal sac and lives in a sound constraining environment along river banks where it competes with other calling frogs. Despite these constraints, male A. franciscus reply acoustically to the calls of conspecifics in the field. To resolve this apparent paradox, we studied the vocal apparatus and middle-ear, analysed signal content of the calls, examined sound and signal content propagation in its natural habitat, and performed playback experiments. We show that A. franciscus males can produce only low intensity calls that propagate a short distance (<8 m) as a result of the lack of an external vocal sac. The species-specific coding of the signal is based on the pulse duration, providing a simple coding that is efficient as it allows discrimination from calls of sympatric frogs. Moreover, the signal is redundant and consequently adapted to noisy environments. As such a coding system can be efficient only at short-range, territory holders established themselves at short distances from each other. Finally, we show that the middle-ear of A. franciscus does not present any particular adaptations to compensate for the lack of an external tympanum, suggesting the existence of extra-tympanic pathways for sound propagation.


Asunto(s)
Anuros/fisiología , Oído Medio/fisiología , Ruido , Vocalización Animal/fisiología , Animales , Anuros/anatomía & histología , Oído Medio/anatomía & histología , Femenino , Masculino
13.
Pediatr Blood Cancer ; 44(7): 673-5, 2005 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15515042

RESUMEN

Occurrence of second cancers is a major concern for the care of children cured of cancer. Children treated for acute lymphoblastic leukemia (ALL) have an increased risk for developing mucoepidermoid carcinomas (MEC) of the parotid gland. The latent period ranges from 5 to 16 years. A 3-year-old boy presented with pre-B ALL. Treatment included multidrug chemotherapy and prophylactic intrathecal injections of methotrexate and prednisolone. Low-grade MEC of the left parotid gland was diagnosed at the age of 7 years, only 1 year after completing treatment. Local lymph nodes were not metastatic, and course was favorable 8 years after complete surgical excision. This case report is remarkable for the early diagnosis of second cancer, only 4 years after diagnosis of ALL, and its occurrence in parotid gland without previous head and neck irradiation. It highlights the need for concern about second cancers of the parotid gland in children treated for ALL.


Asunto(s)
Carcinoma Mucoepidermoide/etiología , Neoplasias Primarias Secundarias/etiología , Neoplasias de la Parótida/etiología , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Mucoepidermoide/patología , Preescolar , Humanos , Masculino , Neoplasias de la Parótida/patología
14.
Cleft Palate Craniofac J ; 42(1): 51-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15643915

RESUMEN

OBJECTIVE: The nasal dermoid sinus cyst (NDSC) is an uncommon congenital lesion presenting as a large panel of midline craniofacial anomalies. The objective of this study was to review and reanalyze embryological hypotheses concerning NDSCs and to propose an embryological theory unifying the various anatomical characteristics of these lesions. The first case of frontal localization of a NDSC extending within the diploetic bone in a 9-month-old boy, presenting as a median frontal fistula with recurrent frontal swelling, 6 months after a mild frontal trauma is presented. RESULTS: Complete surgical removal was performed, and there was no evidence of either persistent or recurrent disease 2 years after his surgery. The embryological and anatomical origins of NDSCs are reviewed. This article reexamines and discusses major embryological theories on NDSC pathogenesis and proposes to refute the "prenasal space" theory of Grunwald and rehabilitate a forgotten embryological hypothesis, which unifies the main various clinical presentations of NDSCs.


Asunto(s)
Quiste Dermoide/congénito , Neoplasias Nasales/congénito , Quiste Dermoide/embriología , Ectodermo , Humanos , Lactante , Masculino , Cresta Neural , Neoplasias Nasales/embriología
15.
Pediatr Dev Pathol ; 6(6): 495-510, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15018449

RESUMEN

We define the histopathologic findings and review the clinical and radiologic characteristics of rapidly involuting congenital hemangioma (RICH). The features of RICH are compared to the equally uncommon noninvoluting congenital hemangioma (NICH) and common infantile hemangioma. RICH and NICH had many similarities, such as appearance, location, size, and sex distribution. The obvious differences in behavior served to differentiate RICH, NICH, and common infantile hemangioma. Magnetic resonance imaging (MRI) of the three tumors is quite similar, but some RICH also had areas of inhomogeneity and larger flow voids on MRI and arterial aneurysms on angiography. The histologic appearance of RICH differed from NICH and common infantile hemangioma, but some overlap was noted among the three lesions. RICH was composed of small-to-large lobules of capillaries with moderately plump endothelial cells and pericytes; the lobules were surrounded by abundant fibrous tissue. One-half of the specimens had a central involuting zone(s) characterized by lobular loss, fibrous tissue, and draining channels that were often large and abnormal. Ancillary features commonly found were hemosiderin, thrombosis, cyst formation, focal calcification, and extramedullary hematopoiesis. With one exception, endothelial cells in RICH (as in NICH) did not express glucose transporter-1 protein, as does common infantile hemangioma. One RICH exhibited 50% postnatal involution during the 1st year, stopped regressing, was resected at 18 months, and was histologically indistinguishable from NICH. In addition, several RICH, resected in early infancy, also had some histologic features suggestive of NICH. Furthermore, NICH removed early (2-4 years), showed some histologic findings of RICH or were indistinguishable from RICH. We conclude that RICH, NICH, and common infantile hemangioma have overlapping clinical and pathologic features. These observations support the hypothesis that these vascular tumors may be variations of a single entity ab initio. It is unknown whether the progenitor cell for these uncommon congenital vascular tumors is the same as for common infantile hemangioma.


Asunto(s)
Hemangioma/congénito , Hemangioma/patología , Neoplasias Cutáneas/congénito , Neoplasias Cutáneas/patología , Niño , Preescolar , Femenino , Hemangioma/diagnóstico por imagen , Humanos , Lactante , Recién Nacido , Masculino , Radiografía , Neoplasias Cutáneas/diagnóstico por imagen
16.
West Indian med. j ; 48(suppl.3): 16, July 1999.
Artículo en Inglés | MedCarib | ID: med-1213

RESUMEN

PURPOSE: The seriousness of ocular alkali burns has been linked to the rapidity with which the alkali enters the eye. The authors report the results of an experimental study on intraocular ammonia penetration. MATERIALS AND METHODS: 23 eyes of New Zealand albino rabbits were burned by applying for one minute 100 ul of a solution titrating 15.3 percent of ammonia. A pH meter probe was inserted into the anterior chamber beforehand to permit pH measurements every 5 seconds. Experiments were carried out after 1,3,5,10 and 30 minutes. The ammonia concentration was measured at the end of the experiment by puncturing the anterior chamber. RESULTS: The pH increased 1 to 3 minutes after applying ammonia on the cornea, reaching a maximum (mean) of 10 five to six minutes later, before an exponential decrease. After 30 minutes, the pH was always more than the physiological pH. The penetration ratio of ammonia through the cornea is about 11 percent. At 30 minutes, the concentration of ammonia is low. The pH observed differs from the calculated pH. DISCUSSION: The difference between observed and calculated pH indicates increases with an intervening plateau, showing the existence of two successive acid-base chemical reactions between ammonia and two types of acid. In addition, the amount of protein destroyed by ammonia can be calculated. CONCLUSIONS: These data show for the time the possibility of calculating the density of proteins destroyed in vivo by a base penetrating the anterior chamber. This opens the possibilty of interesting research work, because it is possible to relate the density of proteins destroyed in the eye to the pK of this base, and to forecast the potential danger of a base of biological tissues.(AU)


Asunto(s)
21003 , Humanos , Quemaduras Oculares/terapia , Quemaduras Químicas/terapia , Sustancias Tóxicas , Estudios de Casos y Controles , Amoníaco
17.
West Indian med. j ; 48(suppl.3): 16, July 1999.
Artículo en Inglés | MedCarib | ID: med-1214

RESUMEN

PURPOSE: The authors present the results of an experimental study to support the proposal for a delay in ocular bathing in the treatment of severe ocular burns due to ammonia. This study compares two solution of ocular wash: physiological serum and Diphoterine. MATERIALS AND METHODS: 23 eyes of New Zealand albino rabbits were burned for one minute by 100 ul of a solution containing 15.3 percent ammonia. Then, each eye was washed by an ocular wash of 250 ml of physiological serum, or of 250 ml of Diphoterine, after a delay of 1,3,5,10 and 30 minutes. The effects were appraised by measuring the anterior chamber, the concentration of ammonia in the anterior chamber, and by the cytopathological analysis of these burned corneas. RESULTS: An ocular wash with Diphoterine in the first few minutes following an ocular burn induces an inflexion of the pH graph, contrary to an ocular wash with physiological serum. On the other hand, there is no inflexion of the pH graph at 30 minutes, and the concentration of ammonia in the anterior chamber is low at that time. The cytopathological analysis shows stromal oedema with the ocular wash by physiological serum, but not when Diphoterine ocular wash is used. DISCUSSION AND CONCLUSIONS: This study proves the importance of ocular bathing in the first minutes following an ocular burn by ammonia. The efficacy of an external ocular wash by Diphoterine features; the importanve of sequelae has been linked to the initial stromal oedema.(AU)


Asunto(s)
21003 , Humanos , Quemaduras Oculares/terapia , Quemaduras Químicas/terapia , Amoníaco
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