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1.
Braz J Biol ; 84: e265278, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36228229

RESUMEN

The contamination of natural resources with heavy metals released from steel mills is the primary cause of soil and water pollution in the Dargai Malakand, located on the northern side of Pakistan. Therefore, the present study was aimed to determine the level of heavy metals in soil and water samples of this area. The wild plant growing (nine native plants: Pteris vittata, Populus nigra, Eucalyptus camaldulensis, Persicaria maculosa, Arundo donax, Xanthium strumarium, Verbascum thapsus, Ricinus communis and Parthenium hysterophorus) there were then tested for their phytoremediation capabilities which is an environmentally friendly, generally utilized, and low-cost approach to eliminate heavy metals from polluted soils and water. Soil, water, and effluent samples were taken from the contaminated sites of seven steel mills in Dargai District Malakand and subjected to heavy metals analysis. Based on bioconcentration factor (BCF) and translocation factor (TF) calculated, The highest BCF for zinc was recorded for Pteris vittata roots (3.93), while the lowest value was observed for Verbascum thapsus leaves (0.306). Pteris vittata root showed the highest BCF for iron (1.618), while Ricinus communis leaves showed the lowest (0.023). The highest BCF value for chromium was highest for Populus nigra roots (0.717), while the lowest value was recorded for Persicaria maculosa leaves (0.031). For the selected metals; Fe, Zn and Cr the highest TF were recorded for Pteris vittata (0.988), Verbascum thapsus (0.944) and Xanthium strumairum (0.968) respectively. Therefore, it is recommended that these plants should be grown near to steel mills to reclaim heavy metals from industrial effluent, polluted soil as well as from polluted water.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Cromo/análisis , Hierro/análisis , Metales Pesados/análisis , Pakistán , Plantas , Ricinus , Suelo , Contaminantes del Suelo/análisis , Acero/análisis , Agua , Zinc/análisis
2.
Nonlinear Dynamics Psychol Life Sci ; 23(2): 177-197, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30898191

RESUMEN

In the present paper, the Rosenzweig-MacArthur predator-prey model (RM), which is a bitrophic food chain model, is considered. We develop the model by adding two assumptions. First, we assume that both species are of economic interest, that is can be harvested. Second, we assume that each specie has its own time scale which range from fast for the prey to slow for the predator. We consider that both the death rate and the catch of the predator are very small which leads to a fast-slow dynamical system. That is, the RM model is transformed into a singular perturbed system with a perturbation parameter E in the set [0,1]. The existence and stability of equilibria are discussed for E > 0. The model experiences both transcritical and Hopf bifurcations for E>0. The singular perturbation model at E = 0 is discussed by separating the system into two subsystems; fast and slow and studying them simultaneously. When 0

Asunto(s)
Cadena Alimentaria , Modelos Biológicos , Conducta Predatoria , Animales , Matemática , Dinámica Poblacional
3.
J Mater Sci Mater Med ; 20(12): 2385-94, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19579061

RESUMEN

Glasses having a chemical composition based on combeite [Na(2)Ca(2)Si(3)O(9)]-fluoroapatite [Ca(5)(PO(4))(3)F] and forsterite [Mg(2)SiO(4)] system were crystallized through controlled heat-treatment. Two forms of sodium calcium silicate e.g. combeite Na(2)Ca(2)Si(3)O(9) and pectolite Na(2)CaSi(3)O(8), were formed together with diopside (CaMgSi(2)O(6)) and monticellite (CaMgSiO(4)) in addition to fluoroapatite (Ca(5)(PO(4))(3)F) phases by thermal treatment of the glasses. Selected glass-ceramics were exposed to a simulated body fluid solution (SBF) which is close to human plasma for 3 weeks. Energy dispersive X-ray analysis (EDX) and inductive coupled plasma (ICP) analysis confirmed the formation of an apatite layer which indicate bioactivity in the all crystallized sample. A decreasing of surface bioactivity with increasing Mg(2)SiO(4)/Na(2)Ca(2)Si(3)O(9) replacement was observed as indicated by the decrease in the amount of apatite layer on the surface of the crystallized specimens. The Vicker's microhardness of the studied glass-ceramic materials are between 5,047 and 6,781 MPa.


Asunto(s)
Apatitas/química , Cerámica , Vidrio , Silicatos/química , Compuestos de Silicona/química , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Rastreo , Difracción de Rayos X
4.
Eur J Haematol ; 65(2): 144-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10966177

RESUMEN

We describe the clinical presentation and course of a patient with autoerythrocyte sensitization (Gardner-Diamond) syndrome, and review the literature for similar cases. A 37-yr-old female presented with recurrent episodes of painful ecchymotic bruising over the anterior aspect of both thighs. These episodes were precipitated by emotional stress. The diagnosis was confirmed by induction of similar lesions by intradermal injection of the patient's own washed red blood cells and hemoglobin. The lesions did not recur for 6 months after the cause of her emotional stress was relieved. Autoerythrocyte sensitization (Gardner-Diamond) syndrome should be considered in the differential diagnosis of purpura, especially in patients with psychiatric problems.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Eritrocitos/inmunología , Adulto , Enfermedades Autoinmunes/diagnóstico , Equimosis/inmunología , Femenino , Humanos , Púrpura/inmunología
6.
Dermatol Surg ; 24(5): 561-5, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9598012

RESUMEN

BACKGROUND: The term Marjolin ulcer is now synonymous with malignant transformation of chronic ulcers, sinus tracts, and burn scars. OBJECTIVE: To illustrate the importance of incisional or excisional biopsies in cases of suspected burn scar carcinoma. METHODS: Case report and review of the literature. RESULTS: Multiple punch biopsies were negative while a complete excision revealed the diagnosis of squamous cell carcinoma. CONCLUSION: Because of the focal nature of malignant change in burn scars, incisional or excisional biopsy should be performed.


Asunto(s)
Quemaduras/complicaciones , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/cirugía , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirugía , Cicatriz/complicaciones , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/cirugía , Abdomen , Carcinoma in Situ/etiología , Carcinoma de Células Escamosas/etiología , Humanos , Masculino , Persona de Mediana Edad , Cirugía de Mohs , Neoplasias Postraumáticas/diagnóstico , Neoplasias Postraumáticas/cirugía , Piel/patología , Neoplasias Cutáneas/etiología , Trasplante de Piel
7.
J Dermatol Surg Oncol ; 19(6): 582-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8389775

RESUMEN

A patient with Klippel-Trenaunay syndrome who developed basal cell and squamous cell carcinomas on the limb affected by the vascular malformation, is reported. The nature of this association is discussed.


Asunto(s)
Carcinoma Basocelular/complicaciones , Carcinoma de Células Escamosas/complicaciones , Síndrome de Klippel-Trenaunay-Weber/complicaciones , Neoplasias Primarias Secundarias , Neoplasias Cutáneas/complicaciones , Adulto , Femenino , Humanos , Pierna
8.
J Am Acad Dermatol ; 25(1 Pt 1): 47-9, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1880253

RESUMEN

Seven patients with basal cell carcinomas presenting as nonhealing ulcers are reported. The importance of considering malignancy and taking biopsy specimens of leg ulcers that fail to respond to treatment is emphasized.


Asunto(s)
Carcinoma Basocelular/complicaciones , Úlcera de la Pierna/complicaciones , Neoplasias Cutáneas/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Basocelular/patología , Enfermedad Crónica , Femenino , Humanos , Úlcera de la Pierna/patología , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/patología , Úlcera Varicosa/complicaciones , Cicatrización de Heridas
9.
J Dermatol Surg Oncol ; 16(10): 945-54, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2229637

RESUMEN

Management of the aging face involves evaluation of the degree of solar elastosis, rhytidosis, and the structural changes associated with senescent skin. Chemical facial exfoliation is divided into deep, medium, and superficial based upon depth of penetration of the caustic agent used. Knowledge of the appropriate indications and technique are essential in obtaining optimal clinical results.


Asunto(s)
Quimioexfoliación , Envejecimiento de la Piel , Quimioexfoliación/métodos , Femenino , Humanos , Persona de Mediana Edad , Piel/patología , Envejecimiento de la Piel/efectos de los fármacos
11.
Int J Dermatol ; 29(5): 333-6, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2193896

RESUMEN

Two cases of acrokeratoelastoidosis comprised of smooth shiny papules on the hands, feet and legs, are reported. Focal acral hyperkeratosis, degenerative collagenous plaques of the hands and keratoelastoidosis marginalis of the hands are three closely related conditions.


Asunto(s)
Enfermedades de la Piel/patología , Adulto , Diagnóstico Diferencial , Tejido Elástico/patología , Epidermis/patología , Femenino , Humanos , Queratosis/patología , Nitrógeno/uso terapéutico , Enfermedades de la Piel/tratamiento farmacológico , Enfermedades de la Piel/etiología
12.
J Dermatol Surg Oncol ; 16(5): 413-8, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2187914

RESUMEN

A small subset of patients with thin (less than 0.76 mm thick) primary cutaneous malignant melanomas develop metastases. Features that may help differentiate higher and lower risk lesions in this thickness range are reported to include the patient's age and sex, anatomic site and diameter of the primary lesion, Clark level of invasion, development of a vertical growth phase, the mitotic index, ulceration, regression, and cellular aneuploidy. In this report, we review the literature regarding the significance of these factors on the patient's prognosis.


Asunto(s)
Melanoma/patología , Neoplasias Cutáneas/patología , Femenino , Humanos , Masculino , Melanoma/secundario , Pronóstico
13.
J Am Acad Dermatol ; 22(4): 594-8, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2319020

RESUMEN

Three clinicopathologic variants of lichen planopilaris are described. The first is characterized clinically by individual keratotic follicular papules and histologically by a lichenoid inflammatory cell infiltrate confined to the follicular epithelium. The second variant consists of erythematous to violaceous plaques, some of which show follicular prominence; the histologic appearance is that of a lichenoid inflammatory cell infiltrate that affects both follicular and interfollicular areas. The third variant manifests as follicular papules of the scalp with concomitant or subsequent cicatricial alopecia. In this variant the histologic hallmark is a lichenoid, follicular and interfollicular inflammation, associated with or followed by scarring. Overlap among the three variants exists, and hence the concept of a disease spectrum ranging from pure follicular involvement without evidence of clinical scarring to cicatricial alopecia of the scalp is advocated.


Asunto(s)
Liquen Plano/patología , Adulto , Anciano , Epidermis/patología , Epitelio/patología , Femenino , Fibrosis , Humanos , Hiperplasia , Masculino , Persona de Mediana Edad , Cuero Cabelludo/patología
18.
J Am Acad Dermatol ; 20(2 Pt 1): 226-31, 1989 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2915056

RESUMEN

The clinical and histopathologic features of actinic lichen planus in 16 patients were studied. The majority of the patients were young, and men and women were almost equally affected. The relative incidence of this condition, compared with the incidence of all forms of lichen planus, was smaller than that reported in the literature. The eruption was distributed over sun-exposed areas, with particular predilection for the face. Covered areas and mucous membranes were spared except for one patient who had involvement of the vermilion border of the lower lip. In most cases the lesions consisted of erythematous brownish plaques with an annular configuration. Less commonly, discrete and confluent papules and hypermelanotic patches, sometimes assuming a melasma-like appearance, were present. The prominent histopathologic features consisted of an interface dermatitis characterized by coarse vacuolar degeneration of the basal cell layer, a mid-dermal perivascular predominantly lymphocytic inflammatory cell infiltrate, and a significant degree of pigment incontinence. Parakeratosis, eczematous changes confined to the follicular epithelium, and a variable degree of solar elastosis were seen in some patients. Mucin deposition was noted in the reticular dermis in two cases.


Asunto(s)
Liquen Plano/patología , Adolescente , Adulto , Dermatosis Facial/patología , Femenino , Antebrazo , Dermatosis de la Mano/patología , Humanos , Hiperplasia/patología , Masculino , Persona de Mediana Edad , Trastornos de la Pigmentación/patología
19.
Cutis ; 41(4): 273-5, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3366012

RESUMEN

An asymptomatic nodule over the right labium majus of a 13-year-old girl is described. Examination of an excisional biopsy specimen revealed a well-circumscribed lobular mass of calcium deposits. No underlying laboratory abnormalities were detected. The lesion most likely represents the female counterpart of idiopathic scrotal calcinosis.


Asunto(s)
Calcinosis/patología , Enfermedades de la Vulva/patología , Adolescente , Femenino , Enfermedades de los Genitales Masculinos/patología , Humanos , Masculino , Escroto
20.
J Am Acad Dermatol ; 18(2 Pt 1): 275-8, 1988 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3346411

RESUMEN

Three cases of actinic lichen planus mimicking melasma are presented. Although the clinical similarity to melasma is striking, the histopathologic picture is distinctive. It is suggested that actinic lichen planus be considered in the differential diagnosis of melasma.


Asunto(s)
Liquen Plano/diagnóstico , Melanosis/diagnóstico , Adulto , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Liquen Plano/patología , Persona de Mediana Edad , Piel/patología , Luz Solar
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