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2.
Med Hypotheses ; 78(4): 450-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22289341

RESUMO

Since the discovery of the genetic code, Mendel's heredity theory and Darwin's evolution theory, science believes that adaptations to the environment are processes in which the adaptation of the genes is a matter of probability, in which finally the specie will survive which is evolved by chance. We hypothesize that evolution and the adaptation of the genes is a well-organized fully adaptive system in which there is no rigidity of the genes. The dividing of the genes will take place in line with the environment to be expected, sensed through the mother. The encoding triplets can encode for more than one amino acid depending on the availability of the amino acids and the needed micronutrients. Those nutrients can cause disease but also prevent diseases, even cancer and auto immunity. In fact we hypothesize that auto immunity is an effective process of the organism to clear suboptimal proteins, formed due to amino acid and micronutrient deficiencies. Only when deficiencies sustain, disease will develop, otherwise the autoantibodies will function as all antibodies function, in a protective way. Furthermore, we hypothesize that essential amino acids are less important than nonessential amino acid (NEA). Species developed the ability to produce the nonessential amino acids themselves because they were not provided by food sufficiently. In contrast essential amino acids are widely available, without any evolutionary pressure. Since we can only produce small amounts of NEA and the availability in food can be reasoned to be too low they are still our main concern in amino acid availability. In conclusion, we hypothesize that increasing health will only be possible by improving our natural environment and living circumstances, not by changing the genes, since they are our last line of defense in surviving our environmental changes.


Assuntos
Adaptação Biológica/genética , Aminoácidos/genética , Autoimunidade/genética , Evolução Molecular , Código Genético/genética , Micronutrientes/genética , Modelos Biológicos , Humanos
3.
Med Hypotheses ; 73(4): 498-502, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19608349

RESUMO

Human physiology is supposed to be a complex interaction of regulating processes, in which hormones, genes, their proteins and apoptosis are thought to play a dominant role. We hypothesize that regulation of physiological processes is mainly influenced by amino acids and micronutrients with hormones, proteins, apoptosis and gene modifications being their derivatives. Furthermore, we suppose that the cells power plant, the mitochondrion, is in fact an intracellular bacterium, living in absolute symbiosis. Because of its intracellular existence it depends on the host's micronutrients completely. Within the host these micronutrients regulate their own formation, degradation, uptake and excretion. Known deficiencies, such as iodine and vitamin D, affect billions of people. Many micronutrients neither have been investigated, nor have they been studied in relation to each other and solid data are not available. Optimal levels of many micronutrients and all amino acids are not known. Amino acids, vitamins and minerals are capable of altering gene expression, inducing apoptosis and regulating chemical processes. It makes them highly attractive for creating better health, against low cost, as we have already proven in the case of rickets, cretinism and scurvy in severe deficiencies. By creating optimal living conditions and study mitochondria from a symbiotic point of view we suppose that diseases not only can be prevented, but the course of diseases can be altered as well.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos Celulares , Alimentos , Regulação da Expressão Gênica/fisiologia , Modelos Biológicos , Animais , Retroalimentação/fisiologia , Humanos
5.
Med Hypotheses ; 71(5): 645-8, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18703293

RESUMO

Recent reports of the World Health Organization show iodine deficiency to be a worldwide occurring health problem. As iodine status is based on median urinary iodine excretion, even in countries regarded as iodine sufficient, a considerable part of the population may be iodine deficient. Iodine is a key element in the synthesis of thyroid hormones and as a consequence, severe iodine deficiency results in hypothyroidism, goiter, and cretinism with the well known biochemical alterations. However, it is also known that iodine deficiency may give rise to clinical symptoms of hypothyroidism without abnormality of thyroid hormone values. This led us to the hypothesis that iodine deficiency may give rise to subtle impairment of thyroid function leading to clinical syndromes resembling hypothyroidism or diseases that have been associated with the occurrence of hypothyroidism. We describe several clinical conditions possibly linked to iodine deficiency, a connection that has not been made thus far. In this paper we will focus on the relationship between iodine deficiency and obesity, attention deficit hyperactivity disorder (ADHD), psychiatric disorders, fibromyalgia, and malignancies.


Assuntos
Hipotireoidismo Congênito/diagnóstico , Bócio/diagnóstico , Iodo/deficiência , Iodo/fisiologia , Encéfalo/patologia , Hipotireoidismo Congênito/etiologia , Feminino , Saúde Global , Bócio/etiologia , Humanos , Hipotireoidismo/diagnóstico , Hipotireoidismo/etiologia , Masculino , Modelos Teóricos , Gravidez , Complicações na Gravidez
6.
Mol Cell Biol ; 19(6): 4465-79, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10330186

RESUMO

cdc25C induces mitosis by activating the cdc2-cyclin B complex. The intracellular localization of cyclin B1 is regulated in a cell cycle-specific manner, and its entry into the nucleus may be required for the initiation of mitosis. To determine the cellular localization of cdc25C, monoclonal antibodies specific for cdc25C were developed and used to demonstrate that in human cells, cdc25C is retained in the cytoplasm during interphase. A deletion analysis identified a 58-amino-acid region (amino acids 201 to 258) in cdc25C that was required for the cytoplasmic localization of cdc25C. This region contained a specific binding site for 14-3-3 proteins, and mutations in cdc25C that disrupted 14-3-3 binding also disrupted the cytoplasmic localization of cdc25C during interphase. cdc25C proteins that do not contain a binding site for 14-3-3 proteins showed a pancellular localization and an increased ability to induce premature chromosome condensation. The cytoplasmic localization of cdc25C was not altered by gamma irradiation or treatment with the nuclear export inhibitor leptomycin B. These results suggest that 14-3-3 proteins may negatively regulate cdc25C function by sequestering cdc25C in the cytoplasm.


Assuntos
Proteínas de Ciclo Celular/análise , Citoplasma/química , Interfase , Mitose , Fosfoproteínas Fosfatases/análise , Fosfatases cdc25 , Anticorpos Monoclonais , Western Blotting , Ciclo Celular , Proteínas de Ciclo Celular/imunologia , Proteínas de Ciclo Celular/fisiologia , Ciclina B/metabolismo , Ciclina B1 , Fibroblastos/metabolismo , Citometria de Fluxo , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Mimosina/farmacologia , Sinais de Localização Nuclear , Osteossarcoma/metabolismo , Fosfoproteínas Fosfatases/imunologia , Fosfoproteínas Fosfatases/fisiologia , Plasmídeos , Testes de Precipitina , Ligação Proteica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Recombinantes de Fusão , Frações Subcelulares , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas
7.
Exp Hematol ; 23(1): 41-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7995370

RESUMO

Bone marrow endothelial cells are likely to play an important role in the homing of hematopoietic progenitor cells. In view of analyzing the interactions between endothelial cells and hematopoietic progenitor cells, we studied several methods of isolating endothelial cells from human bone marrow, including fluorescence activated cell sorting (FACS) and separation by immunomagnetic beads. FACS sorting gave the best results as contamination with other cells did not occur. After density-gradient centrifugation of bone marrow aspirates, the mononuclear cell (MNC) fraction was depleted for T cells, B cells, and myeloid cells by immunomagnetic separation. Further enrichment of endothelial cells was achieved by FACS sorting using BNH9 or S-Endo1 monoclonal antibodies (MAbs). These MAbs, in contrast to several other endothelial-cell reactive MAbs, were found to react highly specifically with sinus endothelial cells as tested by immunohistochemistry on bone marrow tissue sections and cell culture preparations and by double-colored FACS analysis on bone marrow MNCs (BMMNC). Sorted cells, which formed 0.05% of the MNC fraction, showed strong intracytoplasmic von Willebrand factor positivity. Ultrastructural analysis revealed cells with endothelial characteristics. Cells were cultured in fibronectin-coated, 24-well culture plates in endothelial-cell culture medium or long-term bone marrow culture medium. After 1 to 3 weeks of culture, a monolayer of spindle-shaped cells developed expressing endothelial cell antigens. Cells could be kept in culture for 4 to 6 weeks. In conclusion, the method described provides highly purified preparations of human bone marrow endothelium that may permit in vitro adhesion experiments with normal and leukemic hematopoietic progenitor cells.


Assuntos
Células da Medula Óssea , Separação Celular/métodos , Anticorpos Monoclonais , Células Cultivadas , Centrifugação com Gradiente de Concentração , Meios de Cultura , Endotélio/citologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Separação Imunomagnética , Microscopia Eletrônica
8.
Exp Hematol ; 21(4): 573-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8462666

RESUMO

In this study we describe a semiautomated clonogenic assay in which human leukemic cell lines (U937 and HL60) are cultured in a semisolid 96-well microtiter culture system and clonogenicity is measured spectrophotometrically in a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT)-assay and sulforhodamine (SRB)-assay. Culture medium with 0.6% (wt/vol) methylcellulose and 10% (vol/vol) fetal calf serum (FCS) appeared to provide optimal culture conditions with a low background absorbance in both colorimetric assays and an optimal linearity between cell number and optical density (OD). An excellent correlation between clonogenic growth of U937 and HL60 cells in the conventional colony-forming unit assay (CFU-assay) and the microtiter CFU-assay was observed. The value of this microtiter CFU-assay was assessed by modulating U937 and HL60 cells with either 1,25(OH)2D3 or cytosine arabinoside (Ara-C). Additionally, the number of living cells was quantitated spectrophotometrically in both MTT- and SRB-assays. Results obtained by either method did not differ significantly (p < 0.001). In liquid culture, however, significantly (p < 0.001) less reduction of cellular growth was observed with 1,25(OH)2D3-modified cells. No significant differences between the liquid and semisolid assay systems could be observed in the presence of Ara-C. In conclusion, the microtiter clonogenic assay provides a rapid and objective way of measuring clonogenic capacity of (leukemic) cell lines. The semiautomated clonogenic assay will be useful to assess large series of immune modulations and/or cytostatic drug screening.


Assuntos
Células Tumorais Cultivadas/patologia , Calcitriol/farmacologia , Células Clonais , Meios de Cultura , Citarabina/farmacologia , Humanos , Técnicas In Vitro , Espectrofotometria
9.
Am J Ophthalmol ; 115(4): 517-23, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-8470726

RESUMO

We conducted a prospective multicenter study of the efficacy of current therapeutic strategies for ocular toxoplasmosis in 149 patients. Treatment consisted of the following three triple-drug combinations: group 1, pyrimethamine, sulfadiazine, and corticosteroids; group 2, clindamycin, sulfadiazine, and corticosteroids; and group 3, trimethoprim, sulfamethoxazole and corticosteroids. Patients with peripheral retinal lesions were not treated systemically. No difference in the duration of inflammatory activity was observed between treated and untreated patients (P = .5). The most important factor predicting the duration of inflammatory activity was the size of the retinal lesion itself, independent of the treatment (P < .001). We found a reduction in size of the retinal inflammatory lesion for 49% of the pyrimethamine-treated patients (17 of 35) compared to 20% of the untreated patients (eight of 41) (P < .01). However, the most frequent occurrence of side effects was also associated with pyrimethamine medication (26%, nine of 35). The mean recurrence rate after three years of follow-up was 49% for all patients (60 of 122 patients), with no differences between treated and untreated patients (P = .6).


Assuntos
Coriorretinite/tratamento farmacológico , Toxoplasmose Ocular/tratamento farmacológico , Adulto , Coriorretinite/parasitologia , Clindamicina/uso terapêutico , Quimioterapia Combinada , Feminino , Seguimentos , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Humanos , Masculino , Estudos Prospectivos , Pirimetamina/efeitos adversos , Pirimetamina/uso terapêutico , Recidiva , Sulfadiazina/efeitos adversos , Sulfadiazina/uso terapêutico , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
10.
Doc Ophthalmol ; 75(3-4): 225-31, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2090396

RESUMO

Analysis of local intraocular antibody production is a valuable tool with which to confirm a suspected clinical diagnosis in uveitis. We have analysed paired serum and aqueous samples for the presence of specific antibodies against toxoplasma, cytomegalovirus, herpes simplex virus and varicella zoster virus. Of the patients retrospectively diagnosed as having toxoplasma chorioretinitis 75% had a positive antibody coefficient indicating specific antibody production in the eye. Local antibody production in the eye directed against CMV confirmed the suspected diagnosis of CMV retinitis in 50% of the AIDS patients investigated. So far we have not been able to demonstrate local antibody production against herpes simplex virus (26 samples tested). Two of three patients with acute retinal necrosis had a positive antibody coefficient against varicella zoster virus. Both of these patients had an even higher titer in the aqueous than in serum. Since the choice of therapy, in infectious uveitis, depends on the causative organisms, it is very important to confirm a suspected clinical diagnosis by means of aqueous humor analysis.


Assuntos
Uveíte/diagnóstico , Anticorpos Antiprotozoários/análise , Anticorpos Antivirais/análise , Humor Aquoso/imunologia , Humanos , Técnicas Imunológicas
11.
Br J Ophthalmol ; 74(6): 344-9, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2198928

RESUMO

In a randomised double-masked study of 27 patients with a severe chronic idiopathic uveitis we evaluated the efficacy, safety, and tolerability of cyclosporin. All received prednisone in a low dose (0.3 mg/kg/day). In 14 patients this was combined with cyclosporin in a single daily dose of 10 mg/kg/day, while 13 patients received a placebo. The dosages were tapered off in accordance with a protocol, and we compared the number of months of successful therapy before the uveitis relapsed. The efficacy results, as expressed in a Kaplan-Meier curve, were in favour of cyclosporin. Owing to the small sample size, however, this difference did not reach statistical significance. The immunosuppressive effect of cyclosporin was not permanent, and in all but one patient the intraocular inflammation relapsed on reduction of dosage. Rather small cumulative doses of cyclosporin proved to be nephrotoxic, but subjective tolerability for cyclosporin was good.


Assuntos
Ciclosporinas/uso terapêutico , Uveíte/tratamento farmacológico , Adulto , Idoso , Doença Crônica , Ciclosporinas/efeitos adversos , Método Duplo-Cego , Tolerância a Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Int Ophthalmol ; 13(6): 383-6, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2697703

RESUMO

Analysis of local toxoplasma antibody production to confirm a suspected clinical diagnosis of toxoplasma chorioretinitis is a valuable diagnostic tool. Determination of toxoplasma antibodies in the blood of the patient is of limited use. When blood toxoplasma tests are negative this indicates that toxoplasma as a causative organisms in the pathogenesis of uveitis is unlikely. A positive blood test is a sensitive test (100% patients positive) but not a specific test since so many healthy individuals already have undergone subclinical infection and have acquired humoral immunity against the parasite. We analysed 93 paired aqueous and serum samples for toxoplasma antibodies and total IgG and determined the Goldmann-Wittmer coefficient. In patients retrospectively diagnosed as having toxoplasma chorioretinitis 16 out of 22 had a positive coefficient, indicating local parasite antibody production. In one patient with AIDS we also found a positive toxoplasma coefficient. Three out of 15 patients with posterior uveitis of unknown origin also had a positive coefficient. None of the cataract patients tested (n = 32) had a positive coefficient. Major drawbacks of aqueous humor analysis are that a false negative antibody coefficient can occur when a massive blood aqueous barrier breakdown has occurred.


Assuntos
Anticorpos Antiprotozoários/análise , Humor Aquoso/imunologia , Coriorretinite/diagnóstico , Toxoplasmose Ocular/diagnóstico , Coriorretinite/sangue , Humanos , Valor Preditivo dos Testes , Toxoplasmose Ocular/sangue
13.
Int Ophthalmol ; 13(6): 415-9, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2697708

RESUMO

We performed a prospective multicentre study to evaluate the efficacy of therapeutic strategies currently used for ocular toxoplasmosis in a large number of patients (n = 106). Treatment was given for at least four weeks and consisted of three triple drug combinations: group 1, pyrimethamine, sulphadiazine and corticosteroids (n = 29); group 2. clindamycin, sulphadiazine and corticosteroids (n = 37); and group 3. cotrimoxazole (trimethoprim and sulphamethoxazole) and corticosteroids (n = 8). Patients with peripheral retinal lesions remained without systemic therapy (group 4, n = 32). Patients from group 1 received leucovorin 5 mg twice a week. No difference in the duration of inflammatory activity was observed between the treated and untreated patients or between the separate groups of patients. The most important factor predicting the duration of inflammatory activity was the size of the retinal focus itself, independently of the therapy given (P less than 0.05). We showed a reduction in size of the retinal inflammatory focus in 52% of the pyrimethamine patients as compared to 25% of untreated cases. However the most frequent side effects were also associated with pyrimethamine medication and included hematologic complications as thrombocytopenia and leucopenia despite leucovorin medication.


Assuntos
Coccidiostáticos/uso terapêutico , Toxoplasmose Ocular/tratamento farmacológico , Coriorretinite/tratamento farmacológico , Clindamicina/efeitos adversos , Clindamicina/uso terapêutico , Coccidiostáticos/efeitos adversos , Quimioterapia Combinada , Humanos , Inflamação/tratamento farmacológico , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Pirimetamina/efeitos adversos , Pirimetamina/uso terapêutico , Retina/efeitos dos fármacos , Retina/patologia , Combinação Trimetoprima e Sulfametoxazol/efeitos adversos , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
14.
Curr Eye Res ; 8(9): 957-62, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2676357

RESUMO

An indirect immunofluorescence test (IIF) using guinea pig lip as a substrate was performed with sera from 10 patients with Behçet's disease and the results were compared to IIF with sera of 16 patients with uveitis of Turkish origin, 62 patients with non- Behçet's uveitis, 9 patients with stomatitis aphtosa and 34 healthy controls. Antibodies to guinea pig lip cytoplasmic antigens were present in 70% of the Behçet patients, in 19% of uveitis patients of Turkish origin (P less than 0.05), in 12% of the non Behçet uveitis patients (P less than 0.001), in 11% of the stomatitis aphtosa patients (P less than 0.05) and in 9% of the healthy controls (P less than 0.001). A positive Behçet serum preincubated with the supernatant of guinea pig lip sections incubated in PBS gave an inhibition on the IIF test, indicating that the antigen involved in a soluble cytoplasmic substance. No significant increase in the presence of antibodies against iris, cornea or retina (mouse eye) were detected in the Behçet sera. Of interest was the finding of a positive reaction in 6 out of 10 patients in the episcleral region of the mouse eye. This positive reaction resembles immune complex like material. Our findings suggest that using the external surface of the guinea pig lip as a substrate is useful in selecting out those patients with Behçet's disease from uveitis patients with an unknown etiology and from patients with aphtous stomatitis.


Assuntos
Síndrome de Behçet/imunologia , Uveíte/imunologia , Adulto , Animais , Síndrome de Behçet/complicações , Síndrome de Behçet/etnologia , Citoplasma/imunologia , Olho/imunologia , Imunofluorescência , Cobaias , Humanos , Lábio/imunologia , Estudos Longitudinais , Masculino , Microscopia de Fluorescência , Uveíte/etnologia , Uveíte/etiologia
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