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1.
Artigo em Inglês, Russo | MEDLINE | ID: mdl-37325830

RESUMO

Modern warfare is characterized by common mine-explosive injuries. The last ones are accompanied by multiple injuries, large area of damage and severe clinical status of victims. OBJECTIVE: To demonstrate treatment of mine-explosive spinal injuries using modern minimally invasive endoscopic techniques. MATERIAL AND METHODS: The authors present 3 victims with various mine-explosive injuries. Endoscopic removal of fragments from the lumbar and cervical spine was successful in all cases. DISCUSSION: Most of victims with injuries of the spine and spinal cord do not require urgent surgery and can underwent surgical treatment after clinical stabilization. At the same time, minimally invasive techniques provide surgical treatment with minimal risk and earlier rehabilitation, as well as reduce the risk of infectious complications associated with foreign bodies. CONCLUSION: Careful selection of patients for spinal video endoscopy will ensure positive outcomes. Minimization of iatrogenic postoperative injuries is especially important in patients with combined trauma. However, well-experienced surgeons should perform these procedures at the stage of specialized medical care.


Assuntos
Traumatismos da Coluna Vertebral , Humanos , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Traumatismos da Coluna Vertebral/cirurgia , Endoscopia/efeitos adversos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia
2.
Artigo em Russo | MEDLINE | ID: mdl-32207709

RESUMO

Both treatment and effective rehabilitation play an important role in preserving the reproductive health of the girl, the future mother. Along with the search for new drug therapies for various gynecological pathologies, it is important to use physical and natural factors that are natural stimuli for the patient's body. AIM: To examine the effect of health resort factors and methods of physiotherapy on the general condition and hormonal status of girls with delayed sexual development. MATERIAL AND METHODS: 83 patients with delayed sexual development who were examined at the children's clinical sanatorium 'Zdravnitsa' in Yevpatoria (Crimea) were examined: 52 girls were included in the primary group, 31 - in the comparison group. Both groups, depending on age, were divided into subgroups: 13-14 years old and 15-17 years old. Patients in both groups received a standard treatment complex (STC). In addition to SCR, the girls of the main group were prescribed: 5% brine electrophoresis by sinusoidal modulated currents, sage and sea baths. The control group included gynecologic ally healthy adolescents: thirteen 13-14 year-old girls old in the subgroup K1 and twelve 15-17 year-old girls in the subgroup K2. Before and after treatment, all patients underwent standard clinical, gynecological, and laboratory examinations. In both groups, the dynamics of clinical and laboratory parameters, as well as gonadotropic and sex steroid hormones in the blood serum were analyzed. RESULTS: The complex of climatic and physical factors had a nonspecific general stimulating effect. There was a positive dynamics in the general condition of patients, their anthropometric indicators, hormonal status, which was more pronounced in the primary group than in the comparison group. Negative dynamics of the course of diseases in girls of both groups was not observed. CONCLUSION: The use of hardware physiotherapy and sage baths increases the effectiveness of STC. The best clinical and laboratory dynamics of the primary indices was noted in patients 13-14 years old than in patients 15-17 years old. The use of natural and preformed physical factors in treatment makes it possible to minimize the drug effect on the body and achieve the most positive treatment results with a minimum of side effects.


Assuntos
Estâncias para Tratamento de Saúde , Modalidades de Fisioterapia , Puberdade Tardia/terapia , Adolescente , Feminino , Humanos , Resultado do Tratamento
3.
Biochemistry (Mosc) ; 77(2): 152-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22348474

RESUMO

A "decoupling effect" (light-induced electron transport without O2 evolution) was observed in Ca-depleted photosystem II (PSII(-Ca)) membranes, which lack PsbP and PsbQ (Semin et al. (2008) Photosynth. Res., 98, 235-249). Here PsbO-depleted PSII (PSII(-PsbO)) membranes (which also lack PsbP and PsbQ) were used to examine effects of PsbO on the decoupling. PSII(-PsbO) membranes do not reduce the acceptor 2,6-dichlorophenolindophenol (DCIP), in contrast to PSII(-Ca) membranes. To understand why DCIP reduction is lost, we studied light effects on the Mn content of PSII(-PsbO) samples and found that when they are first illuminated, Mn cations are rapidly released from the Mn cluster. Addition of an electron acceptor to PSII(-PsbO) samples accelerates the process. No effect of light was found on the Mn cluster in PSII(-Ca) membranes. Our results demonstrate that: (a) the oxidant, which directly oxidizes an as yet undefined substrate in PSII(-Ca) membranes, is the Mn cluster (not the Y(Z) radical or P680(+)); (b) light causes rapid release of Mn cations from the Mn cluster in PSII(-PsbO) membranes, and the mechanism is discussed; and (c) rapid degradation of the Mn cluster under illumination is significant for understanding the lack of functional activity in some PSII(-PsbO) samples reported by others.


Assuntos
Luz , Manganês/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Plantas/metabolismo , Manganês/química , Oxirredução , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/química , Proteínas de Plantas/química , Spinacia oleracea/metabolismo
5.
Mucosal Immunol ; 3(3): 209-12, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20147894

RESUMO

Commensal bacteria are crucial for maturation and function of the mucosal immune system. However, the mechanisms of these interactions are poorly understood. In addition, the role of the composition of the microbiota and the importance of individual species in this community in stimulating different types of immunity are major unanswered questions. We recently showed that the balance between two major effector T cell populations in the intestine, IL-17(+) Th17 cells and Foxp3(+) Tregs, requires signals from commensal bacteria and is dependent on the composition of the intestinal microbiota. Comparison of microbiota from Th17 cell-deficient and Th17 cell-sufficient mice identified segmented filamentous bacteria (SFB) as capable of specifically inducing Th17 cells in the gut. SFB represent the first example of a commensal species that can skew the mucosal effector T cell balance and thus affect the immune fitness of the individual.


Assuntos
Bactérias/imunologia , Imunidade nas Mucosas/imunologia , Intestinos/imunologia , Intestinos/microbiologia , Linfócitos T Reguladores/imunologia , Animais , Bactérias/ultraestrutura , Interleucina-17/imunologia , Intestinos/ultraestrutura , Camundongos , Linfócitos T Reguladores/ultraestrutura
7.
Biochemistry (Mosc) ; 72(11): 1205-15, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18205603

RESUMO

The F(0) fluorescence yield in intact photosystem II (PSII), Ca-depleted PSII (PSII(-Ca/NaCl)), and Mn-depleted PSII membranes was measured before and after dim light treatment (1-2 min), using flash-probe fluorescence and fluorescence induction kinetic measurements. The value of F(0) after the light treatment (F'(0)) was larger than F(0) in dark-adapted PSII membranes and depended on the appearance of the slowly relaxing, reduced plastoquinone pool (t(1/2) = 4 min) formed during preillumination, which was not totally reoxidized before the F'(0) measurement. In PSII(-Ca/NaCl) such a pool also appeared, but the F'(0) yield was even higher than in intact PSII membranes. In Mn-depleted PSII membranes, the pool did not form. Interestingly, the yield of F'(0) in Ca-depleted PSII membranes prepared using chelators (EGTA and citrate) or containing 5 mM EGTA was significantly lower than in PSII(-Ca/NaCl) samples prepared without chelators. These data indicate that chelators inhibit the reduction of Q(A) and Q(B) and formation of the slowly relaxing plastoquinone pool, or alternatively they increase the rate of its oxidation. Such an effect can be explained by coordination of the chelator molecule to the Mn cluster in PSII(-Ca/NaCl) membranes, rather than different amounts of residual Ca2+ in the membranes (with or without the chelator), since the remaining oxygen-evolving activity (approximately 15%) in PSII(-Ca/NaCl) samples did not depend on the presence of the chelator. Thus, chelators of calcium cations not only have an effect on the EPR properties of the S2 state in PSII(-Ca/NaCl) samples, but can also influence the PSII properties determining the rate of plastoquinone pool reduction and/or oxidation. The effect of some toxic metal cations (Cd, Cu, Hg) on the formation of the slowly relaxing pool in PSII membranes was also studied.


Assuntos
Cálcio/metabolismo , Quelantes/farmacologia , Complexo de Proteína do Fotossistema II/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Plastoquinona/metabolismo , Ácido Egtázico/farmacologia , Fluorescência , Cinética , Oxirredução , Fotobiologia , Complexo de Proteína do Fotossistema II/efeitos da radiação , Spinacia oleracea/efeitos dos fármacos , Spinacia oleracea/metabolismo , Spinacia oleracea/efeitos da radiação
8.
Curr Top Microbiol Immunol ; 308: 59-82, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16922086

RESUMO

During fetal development, lymphoid tissue inducer cells (LTis) seed the developing lymph node and Peyer's patch anlagen and initiate the formation of both types of lymphoid organs. In the adult, a similar population of cells, termed lymphoid tissue inducer-like cells (LTi-like cells), supports the formation of organized gut-associated lymphoid tissue (GALT) in the intestine, including both isolated lymphoid follicles (ILFs) and cryptopatches (CPs). Both LTi and LTi-like cells require expression of the transcription factor RORgammat for their differentiation and function, and mice lacking RORgammat lack lymph nodes, Peyer's patches, and other organized GALT. In ILFs and cryptopatches, LTi-like cells are in close contact with different populations of intestinal dendritic cells (DCs), including a subpopulation recently shown to extend dendrites and sample luminal microflora. This interaction may allow for communication between the intestinal lumen and the immune cells in the lamina propria, which is necessary for maintaining homeostasis between the commensal microflora and the intestinal immune system. The potential functional implications of the organization of LTi-like cells, DCs, and lymphocytes in the lamina propria are discussed in the context of maintenance of homeostasis and of infectious diseases, particularly HIV infection.


Assuntos
Intestinos/imunologia , Linfonodos/imunologia , Animais , Células Dendríticas/imunologia , Humanos , Mucosa Intestinal/imunologia , Camundongos , Camundongos Mutantes , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Nódulos Linfáticos Agregados/imunologia , Receptores do Ácido Retinoico/imunologia , Receptores dos Hormônios Tireóideos/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia
9.
Biochemistry (Mosc) ; 69(3): 331-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15061702

RESUMO

Light-induced interaction of Fe(II) cations with the donor side of Mn-depleted photosystem II (PS II(-Mn)) results in the binding of iron cations and blocking of the high-affinity (HAZ) Mn-binding site. The pH dependence of the blocking was measured using the diphenylcarbazide/2,6-dichlorophenolindophenol test. The curve of the pH dependence is bell-shaped with pK1 = 5.8 and pK2 = 8.0. The pH dependence of the O2-evolution mediated by PS II membranes is also bell-shaped (pK2 = 7.6). The pH dependence of the process of electron donation from exogenous donors in PS II(-Mn) was studied to determine the location of the alkaline pH sensitive site of the electron transport chain. The data of the study showed that the decrease in the iron cation binding efficiency at pH > 7.0 during blocking was determined by the donor side of the PS II(-Mn). Mössbauer spectroscopy revealed that incubation of PS II(-Mn) membranes in a buffer solution containing 57Fe(II) + 57Fe(III) was accompanied by binding only Fe(III) cations. The pH dependence of the nonspecific Fe(III) cation binding is also described by the same bell-shaped curve with pK2 = 8.1. The treatment of the PS II(-Mn) membranes with the histidine modifier diethylpyrocarbonate resulted in an increase in the iron binding strength at alkaline pH. It is suggested that blocking efficiency at alkaline pH is determined by competition between OH- and histidine ligand for Fe(III). Because the high-affinity Mn-binding site contains no histidine residue, this fact can be regarded as evidence that histidine is located at another (other than high-affinity) Fe(III) binding site. In other words, this means that the blockage of the high-affinity Mn-binding site is determined by at least two iron cations. We assume that inactivation of oxygen-evolving complex and inhibition of photoactivation in the alkaline pH region are also determined by competition between OH- and a histidine residue involved in coordination of manganese cation outside the high-affinity site.


Assuntos
Ferro/química , Manganês/química , Complexo de Proteína do Fotossistema II/química , Spinacia oleracea/enzimologia , Cátions/química , Cátions/metabolismo , Histidina/química , Histidina/metabolismo , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Cinética , Manganês/metabolismo , Oxirredução , Oxigênio/química , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Ligação Proteica , Espectroscopia de Mossbauer
10.
Biochemistry (Mosc) ; 66(7): 715-20, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11563949

RESUMO

Extraction of the Mn-cluster from photosystem II (PS II) inhibits the main bands of thermoluminescence and induces a new AT-band at -20 degrees C. This band is attributed to the charge recombination between acceptor QA- and a redox-active histidine residue on the donor side of PS II. The effect of Mn(II) and Fe(II) cations as well as the artificial donors diphenylcarbazide and hydroxylamine on the AT-band of thermoluminescence was studied to elucidate the role of the redox-active His residue in binding to the Mn(II) and Fe(II). At the Mn/PS II reaction center (RC) ratio of 90 : 1 and Fe/PS II RC ratio of 120 : 1, treatment with Mn(II) and Fe(II) causes only 60% inhibition of the AT-band. Preliminary exposure of Mn-depleted PS II preparations to light in the presence of Mn(II) and Fe(II) causes binding of the cations to the high-affinity Mn-binding site, thereby inhibiting oxidation of the His residue involved in the AT-band formation. The efficiency of the AT-band quenching induced by diphenylcarbazide and hydroxylamine is almost an order of magnitude higher than the quenching efficiency of Mn(II) and Fe(II). Our results suggest that the redox-active His is not a ligand of the high-affinity site and does not participate in the electron transport from Mn(II) and Fe(II) to YZ. The concentration dependences of the AT-band inhibition by Mn(II) and Fe(II) coincide with each other, thereby implying specific interaction of Fe(II) with the donor side of PS II.


Assuntos
2,6-Dicloroindofenol/metabolismo , Difenilcarbazida/metabolismo , Ferro/metabolismo , Manganês/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , 2,6-Dicloroindofenol/farmacologia , Sítios de Ligação , Difenilcarbazida/farmacologia , Transporte de Elétrons , Ferro/farmacologia , Luz , Manganês/farmacologia , Oxirredução , Complexo de Proteínas do Centro de Reação Fotossintética/efeitos dos fármacos , Complexo de Proteína do Fotossistema II , Spinacia oleracea/metabolismo , Dosimetria Termoluminescente
11.
Biofizika ; 46(3): 482-5, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11449548

RESUMO

Mossbauer spectra of the psaAB mutant of Synechocystis sp. PPC 6803 devoid of photosystem I grown in a 57Fe-containing medium were measured. The spectrum is a broadened doublet whose size (about 20%) and parameters (isomeric shift delta = 0.3 mm/s and quadrupole splitting delta = 0.8 mm/s) suggest the presence of abundant nanoclusters of Fe3+ oxides in a superparamagnetic state tightly bound to the membrane. Treatment of cells with EDTA was accompanied by a substantial (tenfold) decrease in the amount of iron nonspecifically bound to the membrane and the appearance of Fe2+ localized, probably, inside cells and/or cell membranes. In addition, the spectrum of washed cells exhibited superfine magnetic splitting due to iron oxide clusters greater in size than nanoclusters present in the membrane prior to EDTA treatment.


Assuntos
Proteínas de Bactérias/metabolismo , Cianobactérias/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Proteínas de Plantas/metabolismo , Cianobactérias/citologia , Complexos de Proteínas Captadores de Luz , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteína do Fotossistema I , Ficobilissomas , Mutação Puntual , Espectroscopia de Mossbauer
12.
Biochemistry (Mosc) ; 66(5): 520-3, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11405887

RESUMO

Mössbauer spectra of chloroplasts isolated from spinach plants grown in a mineral medium enriched with 57Fe and Mössbauer spectra of native membranes of the thermophilic cyanobacterium Synechococcus elongatus contain a broad asymmetric doublet typical of the iron-sulfur proteins of Photosystem (PS) I. Exposure of chloroplasts to temperatures of 20-70 degrees C significantly modifies the central part of the spectra. This spectral change is evidence of decreased magnitude of the quadrupole splitting. However, the thermally induced doublet (DeltaQ = 3.10 mm/sec and delta = 1.28 mm/sec) typical of hydrated forms of reduced (divalent) inorganic iron is not observed in spinach chloroplasts. This doublet is usually associated with degradation of active centers of ferredoxin, a surface-exposed protein of PS I. The Mössbauer spectra of photosynthetic membranes of spinach chloroplasts and cyanobacteria were compared using the probability distribution function of quadrupole shift (1/2 quadrupole splitting DeltaQ) of trivalent iron. The results of calculation of these functions for the two preparations showed that upon increasing the heating temperature there was a decrease in the probability of the presence of native iron-sulfur centers FX, FA, and FB (quadrupole shift range, 0.43-0.67 mm/sec) in heated preparations. This process was also accompanied by an increase in the probability of appearance of clusters of trivalent iron. This increase was found to be either gradual and continuous or abrupt and discrete in photosynthetic membranes of cyanobacteria or spinach chloroplasts, respectively. The probability of the presence of the iron-sulfur centers FX, FA, and FB in chloroplasts abruptly decreases to virtually to zero within the temperature range critical for inhibition of electron transport through PS I to oxygen. In cyanobacteria, both thermal destruction of iron-sulfur centers of PS I and functional degradation of PS I are shifted toward a higher temperature. The results of this study suggest that the same mechanism of thermal destruction of the PS I core occurs in both thermophilic and mesophilic organisms: destruction of iron-sulfur centers FX, FA, and FB, release of oxidized (trivalent) iron, and its accumulation in membrane-bound iron-oxo clusters.


Assuntos
Cloroplastos/química , Cianobactérias/química , Proteínas Ferro-Enxofre/química , Spinacia oleracea/química , Cianobactérias/citologia , Proteínas Ferro-Enxofre/metabolismo , Luz , Complexo de Proteínas do Centro de Reação Fotossintética/química , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Espectroscopia de Mossbauer , Temperatura
13.
Biofizika ; 45(4): 654-9, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11040972

RESUMO

The dependence of the diffusion current on the depth of immersion of the electrode was studied by polarography using an open platinum electrode. As the electrode was brought from the depth of the liquid phase to its surface, an increase in the current under aerobic conditions was observed, due to diffusion of oxygen through the interface. The formation of lipid monolayers of phosphatidylcholine, stearic acid, hexadecanol, octadecanol, eicosanol, and docosanol on the water surface led to a decrease in diffusion current; the effect being most pronounced at a minimal depth of immersion of the electrode. The maximum value of the relative decrease in diffusion current R was obtained for docosanol monolaers. It was shown that the R value increases with increasing surface pressure in monolayers of phosphatidylcholine and stearic acid. It is assumed that the decrease in diffusion flow of O2 in the presence of monolayers is caused by the formation of an energy barrier that prevents the sorption of O2, which is related to the presence of hydrocarbon chains weakly interacting with oxygen.


Assuntos
Ar , Lipídeos/química , Oxigênio/química , Água , Difusão
14.
FEBS Lett ; 450(1-2): 135-8, 1999 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-10350072

RESUMO

A model description of the Mössbauer spectrum (80 K) of native membranes of the thermophilic cyanobacterium Synechococcus elongatus is suggested on the basis of the known values of quadrupole splitting (deltaE(Q)) and isomer shift (deltaFe) for the iron-containing components of the photosynthetic apparatus. Using this approach, we found that heating the membranes at 70-80 K results in a decrease of doublet amplitudes belonging to F(X), F(A), F(B) and ferredoxin and simultaneous formation of a new doublet with deltaE(Q) = 3.10 mm/s and delta-Fe = 1.28 mm/s, typical of inorganic hydrated forms of Fe2+. The inhibition of electron transfer via photosystem I to oxygen, catalyzed by ferredoxin, occurs within the same range of temperatures. The data demonstrate that the processes of thermoinduced Fe2+ formation and distortions in the photosystem I electron transport in the membranes are interrelated and caused mainly by the degradation of ferredoxin. The possible role of Fe2+ formation in the damage of the photosynthetic apparatus resulting from heating and the action of other extreme factors is discussed.


Assuntos
Cianobactérias/química , Proteínas Ferro-Enxofre/química , Ferro/química , Proteínas de Bactérias/química , Simulação por Computador , Ferredoxinas/química , Temperatura Alta , Proteínas de Membrana/química , Complexo de Proteínas do Centro de Reação Fotossintética/química , Desnaturação Proteica , Espectroscopia de Mossbauer
16.
FEBS Lett ; 375(3): 223-6, 1995 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-7498504

RESUMO

The interaction of Fe(II) and Fe(III) with the 'high-affinity Mn-binding site' in Mn-depleted photosystem II (PSII) was investigated using diphenilcarbazide (DPC)/2,6-dichlorophenol-indophenol (DCIP) inhibition assay. Fe(III) was ineffective in the inhibition of DPC-DCIP reaction while Fe(II) decreased the rate of DCIP photoreduction supported by DPC in the same concentration range as Mn(II). The effectivity of the interaction of Fe(II) with the high affinity Mn-binding site depends on different anions in the same manner as for Mn(II) and coincides with hierarchy observed for the stimulation of O2 evolution. The Fe(II) binding is accompanied by its oxidation. By using reductants it was shown that the high affinity site contains a redox-active component and the reduction of this component totally prevents the binding of Fe(II).


Assuntos
Ferro/metabolismo , Manganês/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/química , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , 2,6-Dicloroindofenol/farmacologia , Sítios de Ligação , Quelantes/farmacologia , Difenilcarbazida/farmacologia , Transporte de Elétrons , Membranas Intracelulares/metabolismo , Cinética , Oxigênio/metabolismo , Complexo de Proteína do Fotossistema II , Spinacia oleracea/metabolismo , Especificidade por Substrato
17.
Gen Physiol Biophys ; 11(3): 229-39, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1426973

RESUMO

Stationary delayed fluorescence (DF) of chlorophyll in isolated membrane preparations from thermophilic cyanobacterium Synechococcus elongatus was investigated as a function of temperature. Two peaks at different temperatures were observed. The low-temperature peak (54-60 degrees C) coincided with the main maximum of the thermally-induced delayed fluorescence of chlorophyll in intact cells and PSII-particles with active oxygen-evolving system. The high-temperature peak (78 degrees C) coincided with the minor band of delayed light emitted by intact cells. It was also observed in the delayed fluorescence emission from a PSI-enriched fraction preparation. The intensities of the DF peaks were dependent on the presence of inhibitors, donors and acceptors that cause specific effects on electron transport of the two photosystems. The low-temperature and high-temperature peaks were related to PSII and PSI, respectively. The manifestation of delayed fluorescence from PSI and PSII at different temperatures seems to be a specific property of thermophilic cyanobacteria. The reason for this may be a high thermal stability of the photosystems and the lack of the PSII antenna complex in isolated membranes. Consequently, the relative yield of delayed fluorescence from PSI markedly increases. Thermally-induced fluorescence seen in membranes of cyanobacteria showed a high sensitivity to structural and functional membrane alterations induced by pH changes, different electron transport stabilizing agents or different concentrations of MgCl2.


Assuntos
Clorofila/metabolismo , Cianobactérias/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Citratos/farmacologia , Ácido Cítrico , Cinética , Complexos de Proteínas Captadores de Luz , Cloreto de Magnésio/farmacologia , Microscopia de Fluorescência , Complexo de Proteínas do Centro de Reação Fotossintética/efeitos dos fármacos , Complexo de Proteína do Fotossistema I , Termodinâmica
18.
Urol Nefrol (Mosk) ; (1): 13-8, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1858197

RESUMO

Hypercalciuria is one of the main causes of recurrent generation of urinary calcium-containing calculi. 107 patients with recurrent calcium nephrolithiasis were examined and results presented. Concentrations of potassium, sodium, chlorides, calcium, phosphorus, uric acid and creatinine were investigated in serum and urine, as well as indices of acid-base balance in arterial blood. pH-metry, "preliminary" and oral calcium tolerance test were also carried out. The microcomputer data analysis established that the diagnosis of primary hyperparathyroidism may be identified in case of increased serum calcium level before and after calcium load test, the same of parathyroid, and increased urinary cAMP excretion. Renal hypercalciuria is characterized by low blood calcium level in both periods of the oral test, high basal calciuria, increased urinary cAMP excretion and its slight decrease after the oral calcium load test, by a tendency to lower serum magnesium levels in high magnesuria. The patients with absorptive hypercalciuria had an upper normal or increased blood calcium level, a significant calcemic and calciuric "response" to the calcium load, reduction in urinary cAMP elimination and more severe decrease (close to 0) of these indices after oral calcium load and normal magnesium levels in blood and urine. On a base of the "preliminary" test data the patients with relapsing calcium nephrolithiasis and metabolic disorders may be differed from those without calcium and phosphorus metabolic deteriorations. The "preliminary" test defines indications for the oral calcium tolerance test, automatic diagnosis and computer data storage facilitate physician to work and to solve problems of the patients' survey.


Assuntos
Cálcio/metabolismo , Cálculos Renais/diagnóstico , Cálcio/análise , Diagnóstico Diferencial , Humanos , Hiperparatireoidismo/diagnóstico , Hiperparatireoidismo/metabolismo , Cálculos Renais/metabolismo , Recidiva
19.
Gen Physiol Biophys ; 9(2): 189-202, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2113502

RESUMO

Thermal stability of the ferricyanide (FC) and dichlorophenolindophenol (DCIP) reducing reactions was investigated in isolated membrane preparations and PS II particles with active water splitting system from the cyanobacterium Synechococcus elongatus. In a hypotonic medium, the thermostability was seen to be much higher for the DCIP than for the FC reduction reaction. After the addition of high concentrations of polyethylene glycol (Mwt = 4000) or sodium citrate to the medium, the FC reduction reaction appeared to be more temperature resistant. Data on the effects of temperature, DCMU and detergents on the electron transfer rate in PS II provide evidence suggesting that the different thermal stabilities of the two reactions are due to different physico-chemical properties of the electron donor sites to FC and DCIP. The data suggest that regions of contact between individual macromolecular complexes of the electron transport chain are the most labile sites of the photosynthetic apparatus. The role of the composition and properties of the intracellular medium on thermostability are emphasized.


Assuntos
Clorofila/metabolismo , Cianobactérias/metabolismo , Proteínas de Plantas/metabolismo , 2,6-Dicloroindofenol/metabolismo , Transporte de Elétrons , Ferricianetos/metabolismo , Temperatura Alta , Membranas Intracelulares/metabolismo , Complexos de Proteínas Captadores de Luz , Oxirredução , Fotossíntese , Complexo de Proteínas do Centro de Reação Fotossintética , Temperatura
20.
Gen Physiol Biophys ; 9(1): 65-70, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2179046

RESUMO

Chloroplasts isolated from pea seadlings grown on water containing 45Ca2+ were treated with local anesthetic tetracaine. Addition of tetracaine inactivated the electron transport activity of donor side photosystem II. This inhibition was accompanied by 45Ca2+ release from the chloroplast membranes as the whole and destroyed by osmotic shock. No such effect was observed when Tris or hydroxylamine were used to inhibit the donor side photosystem II. Upon thermal inactivation of chloroplasts 45Ca2+ release occurred but at temperatures above 80 degrees. The functional role of Ca2+ in photosystem II is discussed.


Assuntos
Cálcio/metabolismo , Cloroplastos/metabolismo , Fabaceae/metabolismo , Plantas Medicinais , Tetracaína/farmacologia , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Cinética , Complexos de Proteínas Captadores de Luz , Complexo de Proteínas do Centro de Reação Fotossintética , Complexo de Proteína do Fotossistema II , Proteínas de Plantas/metabolismo
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