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1.
Braz J Biol ; 84: e265278, 2022.
Article in English | MEDLINE | ID: mdl-36228229

ABSTRACT

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.


Subject(s)
Metals, Heavy , Soil Pollutants , Biodegradation, Environmental , Chromium/analysis , Iron/analysis , Metals, Heavy/analysis , Pakistan , Plants , Ricinus , Soil , Soil Pollutants/analysis , Steel/analysis , Water , Zinc/analysis
2.
Nonlinear Dynamics Psychol Life Sci ; 23(2): 177-197, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30898191

ABSTRACT

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

Subject(s)
Food Chain , Models, Biological , Predatory Behavior , Animals , Mathematics , Population Dynamics
3.
J Mater Sci Mater Med ; 20(12): 2385-94, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19579061

ABSTRACT

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.


Subject(s)
Apatites/chemistry , Ceramics , Glass , Silicates/chemistry , Silicon Compounds/chemistry , Calorimetry, Differential Scanning , Microscopy, Electron, Scanning , X-Ray Diffraction
4.
Eur J Haematol ; 65(2): 144-7, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10966177

ABSTRACT

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.


Subject(s)
Autoimmune Diseases/immunology , Erythrocytes/immunology , Adult , Autoimmune Diseases/diagnosis , Ecchymosis/immunology , Female , Humans , Purpura/immunology
6.
Dermatol Surg ; 24(5): 561-5, 1998 May.
Article in English | MEDLINE | ID: mdl-9598012

ABSTRACT

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.


Subject(s)
Burns/complications , Carcinoma in Situ/diagnosis , Carcinoma in Situ/surgery , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/surgery , Cicatrix/complications , Skin Neoplasms/diagnosis , Skin Neoplasms/surgery , Abdomen , Carcinoma in Situ/etiology , Carcinoma, Squamous Cell/etiology , Humans , Male , Middle Aged , Mohs Surgery , Neoplasms, Post-Traumatic/diagnosis , Neoplasms, Post-Traumatic/surgery , Skin/pathology , Skin Neoplasms/etiology , Skin Transplantation
7.
J Dermatol Surg Oncol ; 19(6): 582-4, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8389775

ABSTRACT

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.


Subject(s)
Carcinoma, Basal Cell/complications , Carcinoma, Squamous Cell/complications , Klippel-Trenaunay-Weber Syndrome/complications , Neoplasms, Second Primary , Skin Neoplasms/complications , Adult , Female , Humans , Leg
8.
J Am Acad Dermatol ; 25(1 Pt 1): 47-9, 1991 Jul.
Article in English | MEDLINE | ID: mdl-1880253

ABSTRACT

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.


Subject(s)
Carcinoma, Basal Cell/complications , Leg Ulcer/complications , Skin Neoplasms/complications , Adult , Aged , Aged, 80 and over , Carcinoma, Basal Cell/pathology , Chronic Disease , Female , Humans , Leg Ulcer/pathology , Male , Middle Aged , Skin Neoplasms/pathology , Varicose Ulcer/complications , Wound Healing
9.
J Dermatol Surg Oncol ; 16(10): 945-54, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2229637

ABSTRACT

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.


Subject(s)
Chemexfoliation , Skin Aging , Chemexfoliation/methods , Female , Humans , Middle Aged , Skin/pathology , Skin Aging/drug effects
11.
Int J Dermatol ; 29(5): 333-6, 1990 Jun.
Article in English | MEDLINE | ID: mdl-2193896

ABSTRACT

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.


Subject(s)
Skin Diseases/pathology , Adult , Diagnosis, Differential , Elastic Tissue/pathology , Epidermis/pathology , Female , Humans , Keratosis/pathology , Nitrogen/therapeutic use , Skin Diseases/drug therapy , Skin Diseases/etiology
12.
J Dermatol Surg Oncol ; 16(5): 413-8, 1990 May.
Article in English | MEDLINE | ID: mdl-2187914

ABSTRACT

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.


Subject(s)
Melanoma/pathology , Skin Neoplasms/pathology , Female , Humans , Male , Melanoma/secondary , Prognosis
13.
J Am Acad Dermatol ; 22(4): 594-8, 1990 Apr.
Article in English | MEDLINE | ID: mdl-2319020

ABSTRACT

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.


Subject(s)
Lichen Planus/pathology , Adult , Aged , Epidermis/pathology , Epithelium/pathology , Female , Fibrosis , Humans , Hyperplasia , Male , Middle Aged , Scalp/pathology
18.
J Am Acad Dermatol ; 20(2 Pt 1): 226-31, 1989 Feb.
Article in English | MEDLINE | ID: mdl-2915056

ABSTRACT

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.


Subject(s)
Lichen Planus/pathology , Adolescent , Adult , Facial Dermatoses/pathology , Female , Forearm , Hand Dermatoses/pathology , Humans , Hyperplasia/pathology , Male , Middle Aged , Pigmentation Disorders/pathology
19.
Cutis ; 41(4): 273-5, 1988 Apr.
Article in English | MEDLINE | ID: mdl-3366012

ABSTRACT

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.


Subject(s)
Calcinosis/pathology , Vulvar Diseases/pathology , Adolescent , Female , Genital Diseases, Male/pathology , Humans , Male , Scrotum
20.
J Am Acad Dermatol ; 18(2 Pt 1): 275-8, 1988 Feb.
Article in English | MEDLINE | ID: mdl-3346411

ABSTRACT

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.


Subject(s)
Lichen Planus/diagnosis , Melanosis/diagnosis , Adult , Biopsy , Diagnosis, Differential , Female , Humans , Lichen Planus/pathology , Middle Aged , Skin/pathology , Sunlight
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