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Drug delivery through electroporation could be highly beneficial for the treatment of different types of diseased tissues within the human body. In this work, a mathematical model of reversible tissue electroporation is presented for injecting drug into the diseased cells. The model emphasizes the tissue boundary where the drug is injected as a point source. In addition, the effect of drug loss at tissue boundaries through extracellular space is studied elaborately. Multiple pulses are applied to deliver a sufficient amount of drug into the targeted cells. The set of differential equations that model the physical circumstances are solved numerically. This model obtains a mass transfer coefficient (MTC), in terms of pore fraction coefficient and drug permeability that controls the drug transport from extracellular to intracellular space. The drug penetration throughout the tissue is captured for the application of different pulses. The boundary effects on drug concentration are highlighted in this study. The advocated model is able to perform homogeneous drug transport into the cells so that the affected tissue is treated completely. This model can be applied to optimize clinical experiments by avoiding the lengthy and costly in vivo and in vitro experiments.
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Semen sexing is among one of the most remarkable inventions of the past few decades in the field of reproductive biotechnology. The urge to produce offspring of a desired sex has remained since traditional times. Researchers have tried many methods for accurate semen sexing, but only the flow cytometry method has proved to be effective for commercial utilization. However, there were always concerns about the effects of sexed semen, especially on fertility and the rate of genetic gain. Some concerns were genuine because of factors such as low semen dosage in sexed semen straws and damage to sperm during the sorting process. Various researchers have conducted numerous studies to find out the effect of sexed semen on fertility and, in this article, we reflect on their findings. Initially, there were comparatively much lower conception rates (â¼70% of conventional semen) but, with refinement in technology, this gap is bridging and the use of sexed semen will increase over time. Concerning genetic gain with use of sexed semen, a positive effect on rate of genetic progress with the use of sexed semen has been observed based on various simulation studies, although there has been a mild increase in inbreeding.
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Fertilidade , Sêmen , Pré-Seleção do Sexo , Animais , Masculino , Bovinos , Feminino , Sêmen/fisiologia , Fertilidade/genética , Pré-Seleção do Sexo/métodos , Espermatozoides/fisiologia , Inseminação Artificial/veterinária , Inseminação Artificial/métodos , GravidezRESUMO
Electroporation is a very useful tool for drug delivery into various diseased tissues of the human body. This technique helps to improve the clinical treatment by transferring drugs into the targeted cells rapidly. In electroporation, drug particles enter easily into the intracellular compartment through the temporarily permeabilized cell membrane due to the applied electric field. In this work, a mathematical model of drug delivery focusing on reversible tissue electroporation is presented. In addition, the thermal effects on the tissue, which is an outcome of Joule heating, are also considered. This model introduces a time-dependent mass transfer coefficient, which is significant to drug transport. Multiple pulses with low voltage are applied to reach sufficient drugs into the targeted cells. Based on the physical circumstances, a set of differential equations are considered and solved. The changes in drug concentration with different parameters (e.g., diffusion coefficient, drug permeability, pulse length, and pulse number) are analyzed. The model optimizes the electroporation parameters to uptake sufficient drugs into the cells with no thermal damage. This model can be used in clinical experiments to predict drug uptake into the infected cells by controlling the model parameters according to the nature of infections.
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Eletroporação , Modelos Teóricos , Humanos , Transporte Biológico , Eletroporação/métodos , Membrana Celular , Eletricidade , Preparações FarmacêuticasRESUMO
Electroporation method is a useful tool for delivering drugs into various diseased tissues in the human body. As a result of an applied electric field, drug particles enter the intracellular compartment through the temporarily permeabilized cell membrane. Consequently, electroporation method allows better penetration of the drug into the diseased tissue and improves treatment clinically. In this study, a more generalized model of drug transport in a single cell is proposed. The model is able to capture non-homogeneous drug transport in the cell due to non-uniform cell membrane permeabilization. Several numerical experiments are conducted to understand the effects of electric field and drug permeability on drug uptake into the cell. Through investigation, the appropriate electric field and drug permeability are identified, which lead to sufficient drug uptake into the cell. This model can be used by experimentalists to get information prior to conduct any experiment, and it may help reduce the number of actual experiments that might be conducted otherwise.
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Terapia com Eletroporação , Eletroporação , Humanos , Transporte Biológico , Eletroporação/métodos , Eletricidade , Membrana Celular/metabolismo , Permeabilidade da Membrana CelularRESUMO
In order to overcome the obstruction of cell membranes in the path of drug delivery to diseased cells, the applications of electric pulses of adequate potency are designated as electroporation. In the present study, a mathematical model of drug delivery into the electroporated tissue is advocated, which deals with both reversibly and irreversibly electroporated cells. This mathematical formulation is manifested through a set of differential equations, which are solved analytically, and numerically, according to the complexity, with a pertinent set of initial and boundary conditions. The time-dependent mass transfer coefficient in terms of pores is used to find the drug concentrations through reversibly and irreversibly electroporated cells as well as extracellular space. The effects of permeability of drug, electric field and pulse period on drug concentrations in extracellular and intracellular regions are discussed. The threshold value of an electric field (E>100 V cm-1) to initiate drug uptake is identified in this study. Special emphasis is also put on two cases of electroporation, drug dynamics during ongoing electroporation and drug dynamics after the electric pulse period is over. Furthermore, all the simulated results and graphical portrayals are discussed in detail to have a transparent vision in comprehending the underlying physical and physiological phenomena. This model could be useful to various clinical experiments for drug delivery in the targeted tissue by controlling the model parameters depending on the tissue condition.
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Preparações Farmacêuticas , Transporte Biológico , Sistemas de Liberação de Medicamentos , Eletroporação , Modelos TeóricosRESUMO
An investigation was conducted to identify polymorphism in mannose-binding lectin 1 (MBL1) gene and its effect on udder health and performance traits in dairy cattle and buffalo of India. Candidate single-nucleotide polymorphism (SNP) c.2534G > A of MBL1 gene was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). All the possible genotypes for SNP c.2534G > A (GG, AG, and AA) were observed in the studied population. However, Sahiwal cows revealed dimorphic pattern (AG and GG). The effect of targeted SNP on incidence of mastitis was evaluated and found to be significant. Animals with GG genotype were less susceptible to clinical mastitis and had comparatively lower somatic cell score (SCS) in Hardhenu cattle (P < 0.01) and Murrah buffalo (P < 0.05). Animals having GG genotype also exhibited significantly (P < 0.05) lower age at first calving (AFC). AG genotyped Murrah buffalo animals revealed significantly higher second lactation milk yield (P < 0.01). GG genotype with SCS and AFC could therefore be exploited as a promising candidate marker for the genetic improvement of udder health and AFC in dairy animals.
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Doenças dos Bovinos , Lectina de Ligação a Manose/genética , Mastite Bovina , Animais , Búfalos/genética , Bovinos/genética , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/genética , Feminino , Genótipo , Lactação , Glândulas Mamárias Animais , Mastite Bovina/epidemiologia , Mastite Bovina/genética , Leite , Polimorfismo de Nucleotídeo ÚnicoRESUMO
The objective of the present study is to mathematically model the integrated kinetics of drug release in a polymeric matrix and its ensuing drug transport to the encompassing biological tissue. The model embodies drug diffusion, dissolution, solubilization, polymer degradation and dissociation/recrystallization phenomena in the polymeric matrix accompanied by diffusion, advection, reaction, internalization and specific/nonspecific binding in the biological tissue. The model is formulated through a system of nonlinear partial differential equations which are solved numerically in association with pertinent set of initial, interface and boundary conditions using suitable finite difference scheme. After spatial discretization, the system of nonlinear partial differential equations is reduced to a system of nonlinear ordinary differential equations which is subsequently solved by the fourth-order Runge-Kutta method. The model simulations deal with the comparison between a drug delivery from a biodegradable polymeric matrix and that from a biodurable polymeric matrix. Furthermore, simulated results are compared with corresponding existing experimental data to manifest the efficaciousness of the advocated model. A quantitative analysis is performed through numerical computation relied on model parameter values. The numerical results obtained reveal an estimate of the effects of biodegradable and biodurable polymeric matrices on drug release rates. Furthermore, through graphical representations, the sensitized impact of the model parameters on the drug kinetics is illustrated so as to assess the model parameters of significance.
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Sistemas de Liberação de Medicamentos/estatística & dados numéricos , Modelos Biológicos , Animais , Disponibilidade Biológica , Transporte Biológico Ativo , Materiais Revestidos Biocompatíveis/química , Simulação por Computador , Portadores de Fármacos/química , Humanos , Conceitos Matemáticos , Dinâmica não Linear , Farmacocinética , Polímeros/químicaRESUMO
The primary aim of liposomal drug delivery is to wisely modulate the drug delivery system in order to target diseased tissues. Temperature-sensitive liposomes function as a prospective weapon to combat toxic side effects corresponding to direct infusion of anticancer drugs. The main objective of the present study is to model liposomal drug release, subsequent drug transport in solid tumour along with integrated actions of tumour cell surface and endosomal events. Generalized mathematical model for liposomal drug delivery is proposed in which vital physical phenomena, such as kinetics of liposome-encapsulated drug, free drug release from liposomes, transport of both liposomal drug and free drug into the tumour compartment, plasma clearance, protein-drug interactions, drug-tumour cell receptor interactions, internalization of drug through endocytosis along with corresponding endosomal events. The model is expressed through a system of coupled partial differential equations along with appropriate set of initial, interface and boundary conditions which is solved numerically. Simulated results are compared with respective existing experimental data to demonstrate the potency and reliability of the proposed model. Graphical representations of time variant concentration profiles are illustrated to understand the underlying phenomena in details. Moreover, the model speaks for the sensitivity of important drug kinetic parameters, such as advection coefficients, drug release coefficient, plasma clearance rate and internalization parameters through graphical portrayals. The proposed model and the simulated results act as a tool in designing a more effective drug delivery system for cancerous tumours.
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Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Liberação Controlada de Fármacos , Modelos Biológicos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Animais , Antineoplásicos/sangue , Transporte Biológico Ativo , Simulação por Computador , Sistemas de Liberação de Medicamentos , Humanos , Lipossomos , Conceitos Matemáticos , Neoplasias/sangue , Dinâmica não LinearAssuntos
Antineoplásicos/uso terapêutico , Proteínas de Fusão bcr-abl/metabolismo , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Estudos Cross-Over , HumanosRESUMO
AIM: The present investigation was to study genetic characteristics of Harnali sheep with respect to growth performance and to estimate genetic parameters. MATERIALS AND METHODS: The 22 years (1992-2013) data of growth traits of a 1603 synthetic population of Harnali sheep maintained at Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, was utilized for this study. A mixed methodology with regression on their dam's weight was used to study the effect of non-genetic factors on growth traits. Heritability, genetic and phenotypic correlations were estimated using paternal half-sib analysis for body weight at various ages and average daily gain (ADG) for different growth periods. RESULT: The overall least squares mean of body weights recorded for birth weight (BW), weaning weight (WW), six months body weight (SMW), one yearling body weight (YBW), average daily gain from birth to 3 months (ADG1) and average daily gain from 3 to 12 months (ADG2) were 3.35±0.05 kg, 12.41±0.08 kg, 16.30±0.12 kg, 21.88±0.08 kg, 100.66±0.86 g/day and 35.07±0.39 g/day, respectively. The effects of year of birth significantly (p<0.01) influenced the BW, WW, SMW, YWB, ADG1 and ADG2. The effects of sex of lamb significantly (p<0.01) influenced the BW, WW SMW, YWB, ADG1 and ADG2. The effects of dam's weight at lambing significantly (p<0.01) influenced BW, WW, SMW, YWB, ADG1 and ADG2. No definite trend was observed over the years for the averages of body weight and gain. The heritability estimates of BW, WW, SMW, YBW, ADG1 and ADG2 were 0.40±0.05, 0.38±0.05, 0.45±0.06, 0.29±0.05, 0.40±0.06 and 0.33±0.02, respectively. The male lambs were significantly heavier than females at all stages of growth. The heritability estimates were moderate for all the growth traits and high genetic correlations of BW and WW with SMW were found. CONCLUSION: Due to high heritability and positive correlations of SMW with other body weights and daily gain, it was concluded that selection on the basis of SMW would be the best approach to improve growth performance in Harnali sheep.
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In the phase 3 Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients (ENESTnd) study, nilotinib resulted in earlier and higher response rates and a lower risk of progression to accelerated phase/blast crisis (AP/BC) than imatinib in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP). Here, patients' long-term outcomes in ENESTnd are evaluated after a minimum follow-up of 5 years. By 5 years, more than half of all patients in each nilotinib arm (300 mg twice daily, 54%; 400 mg twice daily, 52%) achieved a molecular response 4.5 (MR(4.5); BCR-ABL⩽0.0032% on the International Scale) compared with 31% of patients in the imatinib arm. A benefit of nilotinib was observed across all Sokal risk groups. Overall, safety results remained consistent with those from previous reports. Numerically more cardiovascular events (CVEs) occurred in patients receiving nilotinib vs imatinib, and elevations in blood cholesterol and glucose levels were also more frequent with nilotinib. In contrast to the high mortality rate associated with CML progression, few deaths in any arm were associated with CVEs, infections or pulmonary diseases. These long-term results support the positive benefit-risk profile of frontline nilotinib 300 mg twice daily in patients with CML-CP.
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Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide de Fase Crônica/tratamento farmacológico , Pirimidinas/administração & dosagem , Glicemia/metabolismo , Colesterol/sangue , Seguimentos , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Leucemia Mieloide de Fase Crônica/sangue , Leucemia Mieloide de Fase Crônica/mortalidade , Pirimidinas/farmacologia , Medição de Risco , Resultado do TratamentoRESUMO
The present study aims to provide a comprehensive mathematical model for drug release from microparticles to the adjacent tissues. In the elucidation of drug release mechanisms, the role of mathematical modelling has been depicted thereby facilitating the development of new therapeutic drug by a systematic approach, rather than expensive experimental trial-and-error methods. In order to study the whole process, a two-phase mathematical model describing the dynamics of drug transport in two coupled media is presented. Drug release is described taking into consideration both solubilisation dynamics of drug crystallites and diffusion of the solubilised drug through the microparticle. In the coupled media, reversible dissociation/recystallisation processes are taking place. The model has led to a system of partial differential equations that are solved analytically. The model points out the important roles played by the diffusion, mass-transfer and reaction parameters, which are the main architects behind drug kinetics across two layers. The dependence of drug masses on the main parameters is also analysed.
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Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Modelos Teóricos , HumanosRESUMO
BACKGROUND: Liver transplantation (LT) increases the risk of de novo malignancies including skin cancers. However, risk factors for this type of cancers have not been well studied. OBJECTIVE: To determine the incidence of skin cancer in LT recipients, and to identify the risk factors of this type of cancer. METHODS: We identified all adult patients who underwent LT and developed de novo skin cancer post-LT at our institution between 1996 and 2009. We excluded the patients with history of skin cancer prior to LT. We also studied a control group of patients who underwent LT during the same period but did not develop skin cancer; the control group was matched (1:2) for age, gender and geographical place of residence. RESULTS: Over a median (IQR) follow-up of 41.5 (18.0, 98.6) months, 23 (2.3%) of 998 patients developed skin cancer post-LT, of whom 10 were identified with squamous cell carcinoma, 9 with basal cell carcinoma and 4 with melanoma. After adjusting the confounding variables, subjects who had combined liver/kidney transplant had 22 (95% CI: 5.1-99) times higher hazard of skin cancer compared to subjects with LT alone. Furthermore, patients who had non-skin cancer prior to LT had 23 (95% CI: 8.6-60) times higher hazard developing skin cancer after the transplant. Patients with history of alcohol consumption, as the underlying etiology of liver disease, had 4 (95% CI: 1.2-12.9) times higher hazard of developing skin cancer after transplantation. Type or duration of immunosuppression was not associated with increased risk of skin cancer post-LT. The post-LT survival outcome was not affected by the development of de novo skin cancer post-LT. CONCLUSION: Skin cancer is relatively common in LT recipients and should be monitored, particularly in patients with a history of pretransplant malignancy, recipients of combined liver and kidney transplant or having alcoholic cirrhosis as the underlying cause of liver disease.
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Various N-alkyl and N-acyl derivatives of 2-(4-thiazolyl)-1H-benzimidazole, an anthelmintic and systemic fungicide, were synthesized by polymer-supported reactions and screened for their antifungal and antibacterial potency to establish structure-activity relationships.
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Antibacterianos/farmacologia , Antifúngicos/farmacologia , Tiabendazol/análogos & derivados , Tiabendazol/farmacologia , Alternaria/efeitos dos fármacos , Antibacterianos/síntese química , Antifúngicos/síntese química , Aspergillus/efeitos dos fármacos , Bacillus/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Polímeros/química , Pseudomonas/efeitos dos fármacos , Relação Estrutura-Atividade , Tiabendazol/síntese químicaRESUMO
The flow in a thermally driven square cavity with adiabatic top and bottom walls and differentially heated vertical walls for a wide range of Rayleigh numbers (10(3)< or =Ra< or =10(7)) has been computed with a fourth-order accurate higher-order compact scheme, which was used earlier only for the stream-function vorticity (psi-omega) form of the two-dimensional steady-state Navier-Stokes equations. The boundary conditions used are also compact and of identical accuracy. In particular, a compact fourth-order accurate Neumann boundary condition has been developed for temperature at the adiabatic walls. The treatment of the derivative source term is also compact and has been done in such a way as to give fourth-order accuracy and easy assimilation with the solution procedure. As the discretization for the psi-omega formulation, boundary conditions, and source term treatment are all fourth-order accurate, highly accurate solutions are obtained on relatively coarser grids. Unlike other compact solution procedure in literature for this physical configuration, the present method is fully compact and fully higher-order accurate. Also, use of conjugate gradient and hybrid biconjugate gradient stabilized algorithms to solve the symmetric and nonsymmetric algebraic systems at every outer iteration, ensures good convergence behavior of the method even at higher Rayleigh numbers.
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The diterpene cyclase taxadiene synthase from yew (Taxus) species transforms geranylgeranyl diphosphate to taxa-4(5),11(12)-diene as the first committed step in the biosynthesis of the anti-cancer drug Taxol. Taxadiene synthase is translated as a preprotein bearing an N-terminal targeting sequence for localization to and processing in the plastids. Overexpression of the full-length preprotein in Escherichia coli and purification are compromised by host codon usage, inclusion body formation, and association with host chaperones, and the preprotein is catalytically impaired. Since the transit peptide-mature enzyme cleavage site could not be determined directly, a series of N-terminally truncated enzymes was created by expression of the corresponding cDNAs from a suitable vector, and each was purified and kinetically evaluated. Deletion of up to 79 residues yielded functional protein; however, deletion of 93 or more amino acids resulted in complete elimination of activity, implying a structural or catalytic role for the amino terminus. The pseudomature form of taxadiene synthase having 60 amino acids deleted from the preprotein was found to be superior with respect to level of expression, ease of purification, solubility, stability, and catalytic activity with kinetics comparable to the native enzyme. In addition to the major product, taxa-4(5),11(12)-diene (94%), this enzyme produces a small amount of the isomeric taxa-4(20), 11(12)-diene ( approximately 5%), and a product tentatively identified as verticillene ( approximately 1%). Isotopically sensitive branching experiments utilizing (4R)-[4-(2)H(1)]geranylgeranyl diphosphate confirmed that the two taxadiene isomers, and a third (taxa-3(4),11(12)-diene), are derived from the same intermediate taxenyl C4-carbocation. These results, along with the failure of the enzyme to utilize 2, 7-cyclogeranylgeranyl diphosphate as an alternate substrate, indicate that the reaction proceeds by initial ionization of the diphosphate ester and macrocyclization to the verticillyl intermediate, followed by a secondary cyclization to the taxenyl cation and deprotonation (i.e., formation of the A-ring prior to B/C-ring closure). Two potential mechanism-based inhibitors were tested with recombinant taxadiene synthase but neither provided time-dependent inactivation nor afforded more than modest competitive inhibition.
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Diterpenos/química , Isomerases/genética , Paclitaxel/biossíntese , Antineoplásicos/metabolismo , Inibidores Enzimáticos/farmacologia , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Estrutura Molecular , Mutação , Plantas Medicinais , Fosfatos de Poli-Isoprenil/metabolismo , Precursores de Proteínas/genética , Proteínas Recombinantes , Deleção de Sequência , Taxus/enzimologia , Taxus/metabolismoRESUMO
Embryonal rhabdomyosarcoma of the prostate is a rare. Highly malignant tumour. The median age of occurrence is five years, but sporadic cases have been reported in adults' To the best of our knowledge, till date, fewer than ten cases have been reported of which only two are above the age of sixty years. We report a case of embryonal rhabdomyosarcoma of prostate in a patient more than sixty years of age. If one is not aware of this entity, one can make a mistake in the diagnosis as well as treatment.
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Neoplasias da Próstata/diagnóstico , Rabdomiossarcoma Embrionário/diagnóstico , Idoso , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Rabdomiossarcoma Embrionário/diagnóstico por imagem , UltrassonografiaRESUMO
An open comparative trial was conducted in 58 adult obese patients (Body Mass Index > or = 25 kg/square metre). Group I (n = 27), non-drug, was advised diet (1200-1600 cals) and a brisk walk for 30 minutes. Group II, in addition, received Guggulu (Medohar) 1.5-3 gms/day for 30 days. Mean difference in weight loss between Guggulu and non-drug group was 0.32 kg (ns) on day 15 and 0.58 kg on day 30 (ns). The mean weight reduction in patients (> 90 kgs) was 1.92 kg (ns) and 2.25 kg (ns) higher in Guggulu group. All patients weighing > 90 kg lost weight in Guggulu group whilst 3 in non-drug group did not lose weight. Guggulu was tolerated well. The data from this pilot study suggest a synergistic diet-Guggulu interaction over 30 days in patients weighing > 90 kgs which needs to be confirmed in a large placebo controlled study.
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Obesidade/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Adulto , Feminino , Humanos , Masculino , Ayurveda , Pessoa de Meia-Idade , Projetos Piloto , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
We report here a case of right-sided renal cell carcinoma who presented with hypertension and multi-organ metastases. Haematological manifestations noted were erythrocytosis, thrombocytosis and leukaemoid reaction. Of these leukemoid reaction and thrombocytosis are very rare. The patient had hepatosplenomegaly which was found to be congestive in origin due to the pressure of the tumour on the hepatic vein and the inferior vena cava. These rare features make it an unusual case.