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1.
Calcif Tissue Int ; 114(3): 295-309, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38102510

RESUMO

Vascular dysfunction contributes to the development of osteopenia in hypertensive patients, as decreased blood supply to bones results in tissue damage and dysfunction. The effect of anti-hypertensive medicines on bone mass in hypertensive individuals is inconclusive because of the varied mechanism of their action, and suggests that reducing blood pressure (BP) alone is insufficient to enhance bone mass in hypertension. Pentoxifylline (PTX), a hemorheological drug, improves blood flow by reducing blood viscosity and angiogenesis, also has an osteogenic effect. We hypothesized that improving vascular function is critical to increasing bone mass in hypertension. To test this, we screened various anti-hypertensive drugs for their in vitro osteogenic effect, from which timolol and hydralazine were selected. In adult female spontaneously hypertensive rats (SHRs), timolol and hydralazine did not improve vascular function and bone mass, but PTX improved both. In female SHR animals, PTX restored bone mass, strength and mineralization, up to the level of normotensive control rats. In addition, we observed lower blood vasculature in the femur of adult SHR animals, and PTX restored them. PTX also restored the bone vascular and angiogenesis parameters that had been impaired in OVX SHR compared to sham SHR. This study demonstrates the importance of vascular function in addition to increased bone mass for improving bone health as achieved by PTX without affecting BP, and suggests a promising treatment option for osteoporosis in hypertensive patients, particularly at-risk postmenopausal women.


Assuntos
Hipertensão , Pentoxifilina , Humanos , Ratos , Feminino , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Densidade Óssea , Timolol/farmacologia , Timolol/uso terapêutico , Hipertensão/tratamento farmacológico , Ratos Endogâmicos SHR , Pentoxifilina/farmacologia , Hidralazina/farmacologia , Hidralazina/uso terapêutico , Pressão Sanguínea
2.
Cureus ; 13(2): e13337, 2021 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-33747646

RESUMO

All-trans retinoic acid (ATRA) is a derivative of vitamin A and is the mainstay treatment of acute promyelocytic leukemia (APL). Hypercalcemia is a rare yet important side-effect of ATRA, especially when it is used concomitantly with a medication that impedes its metabolism by inhibiting cytochrome P-450 in the liver and thus increasing the duration of exposure to ATRA. Azole antifungal drugs such as voriconazole are frequently used in patients undergoing chemotherapy due to a high incidence of fungal infections. These medications inhibit two vital enzymes of cytochrome P-450, CYP2C9 and CYP3A4, potentiating the effects of ATRA on calcium metabolism. We present a case of a nine-year-old girl who underwent chemotherapy with all-trans retinoic acid for acute promyelocytic leukemia. The patient was given an anti-fungal cover with voriconazole for extensive fungal chest infection simultaneously. She was found to have asymptomatic hypercalcemia on routine follow-up during the consolidation phase. Both medications were stopped. Subsequently, she was admitted to the ward and managed conservatively with hydration. Serum calcium levels were returned to normal within six days after stopping the combination of ATRA and voriconazole. We underscore that the use of anti-fungal medications should be limited while using ATRA. However, strict monitoring must be done when a combination of these drugs is started, if necessary.

3.
Toxicol Sci ; 172(1): 167-180, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31393584

RESUMO

Mycobacterium leprae infection causes bone lesions and osteoporosis, however, the effect of antileprosy drugs on the bone is unknown. We, therefore, set out to address it by investigating osteogenic differentiation from bone marrow (BM)-derived mesenchymal stem cells (MSCs). Out of 7 antileprosy drugs, only clofazimine (CFZ) reduced MSCs viability (IC50 ∼ 1 µM) and their osteogenic differentiation but increased adipogenic differentiation on a par with rosiglitazone, and this effect was blocked by a peroxisome proliferator-activated receptor gamma antagonist, GW9662. CFZ also decreased osteoblast viability and resulted in impaired bone regeneration in a rat femur osteotomy model at one-third human drug dose owing to increased callus adipogenesis as GW9662 prevented this effect. CFZ treatment decreased BM MSC population and homing of MSC to osteotomy site despite drug levels in BM being much less than its in vitro IC50 value. In adult rats, CFZ caused osteopenia in long bones marked by suppressed osteoblast function due to enhanced adipogenesis and increased osteoclast functions. A robust increase in marrow adipose tissue (MAT) by CFZ did not alter the hematologic parameters but likely reduced BM vascular bed leading to osteonecrosis (ON) characterized by empty osteocyte lacunae. However, CFZ had no effect on visceral fat content and was not associated with any metabolic and hematologic changes. Levels of unsaturated fatty acids in MAT were higher than saturated fatty acids and CFZ further increased the former. From these data, we conclude that CFZ has adverse skeletal effects and could be used for creating a rodent ON model devoid of extraskeletal effects.

4.
Cureus ; 11(5): e4759, 2019 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-31363440

RESUMO

Introduction Nocardiosis is a rare opportunistic bacterial infection usually seen in immunosuppressed patients. It is caused by gram-positive, aerobic actinomycetes of the Nocardia genus. The most common site of infection is lungs; but it may affect other organs or even disseminate into blood. Methods In this a 10-year retrospective review, all diagnosed cases of Pulmonary Nocardiosis in a tertiary care hospital were included. The clinical and radiological characteristics, course of complications and lifesaving interventions, and disease outcome were evaluated. Results Among the 55 identified cases, most common risk factor was chronic steroid therapy (n=38; 69.1%). Among respiratory diseases, chronic obstructive pulmonary disease (n=13; 23.6%) and tuberculosis (n=12; 21.8%) were the most common. On chest radiograph, pleural effusion (n=23; 41.8%) and consolidation (n=22; 40.0%) were the common findings. Complications were observed in 32 (58.2%) patients with septicemia and respiratory failure being the most common (n=15; 46.8% in each). Dissemination occurred in 10 (31.2%) patients. The mortality rate of Nocardia is 34.5% (n=19). Conclusion The disease burden of Nocardia is underestimated by clinicians and researchers. Pulmonary Nocardia should always be a differential diagnosis of signs of lower respiratory tract infection and must be excluded in patients not responding to treatment of chronic obstructive pulmonary disease (COPD) and pulmonary tuberculosis. Early recognition and individualized management plan can ensure successful recovery.

5.
J Med Case Rep ; 12(1): 99, 2018 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-29665852

RESUMO

BACKGROUND: Cold agglutinin disease is a rare disorder characterized by an autoimmune hemolytic anemia occurring at low temperatures. Physical examination findings, often limited to acrocyanosis, are combined with a thermal amplitude test to help establish the diagnosis. Thermal amplitude testing determines the highest temperature at which the cold agglutination will occur and is an important parameter in diagnosing cold agglutinin disease. CASE PRESENTATION: Here we describe a 57-year-old white man of German and Nicaraguan descent with known chronic cold agglutinin disease who presented to our ophthalmology clinic for evaluation of a cataract. During routine cataract surgery, the lowered temperature of the conjunctiva from intermittent flow of balanced salt solution at room temperature induced a cold agglutination reaction in conjunctival vessels easily visible under a surgical microscope. CONCLUSIONS: To the best of our knowledge, this method of demonstrating cold agglutinin disease has not been described in the literature and could easily be performed utilizing an ordinary slit lamp. This method could be used as an alternative and rapid screening method for cold agglutinin disease.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Túnica Conjuntiva/irrigação sanguínea , Anemia Hemolítica Autoimune/complicações , Catarata/complicações , Temperatura Baixa/efeitos adversos , Túnica Conjuntiva/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade
6.
Surg Neurol Int ; 8: 116, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28680735

RESUMO

BACKGROUND: Pilocytic astrocytoma (PA) is the most prevalent central nervous system (CNS) tumor in pediatric population and accounts for an approximate of 5-6% of all gliomas. This neoplasm can occur at all levels of the neuraxis, with majority (67%) arising in the cerebellum and optic pathway. PAs are World Health Organization Grade I tumors and are the most benign of all astrocytomas characterized by an excellent prognosis. Other differentials include subependymal giant cell astrocytoma (SEGA), ependymoma, meningioma, and low-grade gliomas such as pilocytic or diffuse astrocytoma; calcification is more commonly regarded as a feature of benign or slow-growing tumors. CASE DESCRIPTION: We present a case of a 17-year-old female presenting with an unusual cause of hydrocephalus, a rare case of a calcified pilocytic astrocytoma as an intraventricular tumor. CONCLUSION: PA rarely presents as an intraventricular tumor and should be included in the differential diagnosis of a large mass with massive intratumoral calcification.

7.
Curr Med Chem ; 24(16): 1645-1670, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28245768

RESUMO

Inflammasomes are multiprotein complexes having nucleotide-binding domain and leucine-rich repeat consisting members along with pyrin and HIN domain family. An inflammasome mainly consists of cytoplasmic sensor molecule, such as NLRP3, the adaptor apoptosisassociated speck-like protein containing caspase recruitment domain) protein along with effector procaspase-1. The inflammasome regulates caspase-1 activation, resulting in secretion of interleukin- 1ß and interleukin-18. The inflammasome activation is linked with infection, stress, or other immunological signals involved in inflammation. The pathophysiological role of NLRP3 inflammasome in immune regulation, inflammatory receptor-ligand interactions, microbial-associated molecular patterns, danger as well as pathogen associated molecular patterns has been demonstrated in last few years. Furthermore, the role of the inflammasome in peripheral and central nervous system involved with cytokine and chemokine inflammatory responses has been demonstrated in preclinical and clinical studies. The understanding of molecular regulation of inflammasome associated pathways is crucial for drug design and delivery. The use of natural product as an alternate therapy is gaining focus because of easy access and cost effectiveness. A number of herbal extracts and its bioactive constituents known as phytochemicals have shown to be effective in inflammatory response mediated by NLRP3 inflammasomes pathways. To understand the interaction of phytochemicals and inflammasome at the molecular level, it is vital to develop effective drugs that can be evaluated further in the clinical settings. Therefore, this review renders an extensive account of all the phytochemicals which are evaluated either in inflammatory experimental animal models or in immortalized human/animal cell lines that modulate NLRP3 inflammasome mediated pathways to mitigate inflammatory responses with the hope that this pathway modulation by phytochemicals may provide a another class of drugs in the armamentarium as well as novel molecular mechanism of natural products targeting NLRP3 inflammasome.


Assuntos
Produtos Biológicos/química , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/uso terapêutico , Humanos , Doenças Metabólicas/tratamento farmacológico , Doenças Metabólicas/metabolismo , Doenças Metabólicas/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/química , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/uso terapêutico , Plantas Medicinais/química , Plantas Medicinais/metabolismo
8.
PLoS One ; 12(2): e0171267, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28152102

RESUMO

Fasciolosis an economically important global disease of ruminants in the temperate and tropical regions, caused by Fasciola hepatica and F. gigantica, respectively, also poses a potential zoonotic threat. In India alone it causes huge losses to stakeholders. Anthelmintics including triclabendazole have been used to control this menace but the emerging resistance against the available compounds necessitates identification of novel and alternative therapeutic measures involving plant derived natural compounds for their anthelmintic potential. Thymoquinone (T) and curcumin (C), the active ingredients of Nigella sativa and Curcuma longa respectively have been used as antiparasitic agents but the information on their flukicidal effect is very limited. Adult flukes of F. gigantica were in vitro exposed to different concentrations of thymoquinone and curcumin separately for 3h at 37+ 1°C. A significant (p<0.05) reduction in the worm motility at 60 µM concentration of both T and C was observed though all the worms remained alive after 3h exposure, whereas the effect on egg shedding was statistically insignificant. Pronounced tegumental disruptions and erosion of spines in the posterior region and around the acetabulum was evident. A significant (p<0.05) decrease in glutathione-S-transferase and superoxide dismutase activity and reduced glutathione (GSH) level was observed, while protein carbonylation increased differentially. A significant inhibition of CathepsinL (CatL) gene expression in thymoquinone treated worms was also evident. Further, in silico molecular docking of T and C with CatL revealed a stronger interaction of curcumin with the involvement of higher number of amino acids as compared to thymoquinone that could be more effective in inhibiting the antioxidant enzymes of F. gigantica. It is concluded that both the compounds understudy will decrease the detoxification ability of F. gigantica, while inhibition of CatL will significantly affect their virulence potential. Thus, both thymoquinone and curcumin appeared to be promising anthelmintic compounds for further investigations.


Assuntos
Antiplatelmínticos/farmacologia , Benzoquinonas/farmacologia , Curcumina/farmacologia , Fasciola/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Testes de Sensibilidade Parasitária
9.
J Parasit Dis ; 40(3): 910-3, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27605808

RESUMO

The digenetic trematodes, Fasciola gigantica and Gigantocotyle explanatum, belonging to the family Fasciolidae and Paramphistomidae respectively, have been often found to concurrently infect the liver of Indian water buffalo Bubalus bubalis, causing serious pathological damage to the vital organ, incurring huge economic losses. In the present study the soluble gene products of both F. gigantica and G. explanatum were analyzed by 2 dimensional polyacrylamide gel electrophoresis. The soluble proteomic profile revealed considerable similarity as well as differences in the size, distribution pattern, total number, the isoelectric point (pI) and molecular weight (Mr) of the resolved polypeptide spots. The maximum number of polypeptide spots with a molecular weight range of >10 to 160 kDa were recorded with a pI range of 7-9 followed by pI range of 5-7, 9-10 and 3-5 in both the parasites. However, considerable variation was recorded in the Mr of the polypeptides belonging to each pI range. The genetic heterogeneity could be an obvious contributing factor for such differences but some polypeptides appeared to be conserved in the two species. The molecular similarities and the habitat preference by these worms may be a consequence of microenvironmental cues that guide these flukes to reach their habitat through different routes and establish a successful host-parasite relationship.

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