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51.
52.
Prostaglandin E1 (PGE1) produced dose-related catalepsy in rats when administered intracerebroventricularly. PGE1 induced catalepsy was significantly inhibited after pretreatment with pharmacological agents known to attenuate central serotonergic and cholinergic activity. It was also inhibited by PGF2 and naloxone. On the contrary, treatments enhancing central dopaminergic activity also reduced the cataleptic effect of PGE1. The results suggest that PGE1 induces catalepsy in rats by modulating activity of central neurotransmitters.  相似文献   
53.
The present study was aimed to evaluate the anticonvulsant activity of 1,2,3,4,6-penta-O-galloyl-β-d-glucopyranose (PGG) isolated from methanolic leaf extracts of Mangifera indica in mice. Anticonvulsant activity of PGG was evaluated against pentylenetetrazole (PTZ)-induced and maximal electroshock (MES)-induced convulsions in mice. Additionally, locomotor activity and GABA levels in the brain were estimated to explore the possible CNS-depressant activity and mechanism behind the anticonvulsant activity, respectively. In these studies, PGG (2.5, 5, and 10 mg/kg, intraperitoneal (i.p.)) showed significant and dose-dependent inhibition of PTZ and MES-induced convulsions. Furthermore, PGG administration showed significant decrease in the locomotor activity as an indication of its CNS-depressant property; also, PGG has significantly increased the GABA levels in the cerebellum and whole brain other than the cerebellum. In conclusion, PGG isolated from M. indica showed potent anticonvulsant activity, and possible mechanism may be due to enhanced GABA levels in the brain.  相似文献   
54.
PURPOSE: Chemoprevention is an upcoming approach to control bladder cancer, which is one of the commonly diagnosed malignancies showing recurrence rate of 70% or even higher. Recently, we observed the in vitro efficacy of silibinin, a flavanolignan, in human bladder transitional cell papilloma RT4 cells. Here, we investigated the antitumor efficacy and associated mechanisms of silibinin in RT4 tumor xenograft. EXPERIMENTAL DESIGN: RT4 tumor xenograft was implanted s.c. in athymic nude mice, and then animals were oral gavaged with silibinin at 100 and 200 mg/kg doses, 5 days/week for 12 weeks. Tumor growth, body weight, and diet consumption were recorded, and tumors were analyzed for proliferation, apoptosis, and angiogenesis biomarkers and molecular alterations by immunohistochemistry, immunoblot analysis, and ELISA. p53 small interfering RNA was used in cell culture to examine the role of p53 in survivin expression. RESULTS: Silibinin feeding inhibited tumor xenograft growth without any gross signs of toxicity. Silibinin decreased tumor volume by 51% to 58% (P 相似文献   
55.
56.
Lerner  RM; Spataro  RF 《Radiology》1984,153(3):643-645
Experience with percutaneous drainage in four cases of splenic abscess is presented. Percutaneous drainage and antibiotics were curative in three of four cases. The one case not adequately treated by antibiotics and percutaneous drainage was also complicated by ascites and multilocular collections. Percutaneous drainage in this case did not adversely affect subsequent curative surgery. Percutaneous catheter drainage of splenic abscess under radiologic guidance can be a safe, effective treatment.  相似文献   
57.
Recent studies suggest a link between neuropsychiatric disorders and HIV/SIV infection. Most evidence indicates that monocytes/macrophages are the primary cell type infected within the CNS and that they contribute to CNS inflammation and neurological disease. Substance P (SP), a pleotropic neuropeptide implicated in inflammation, depression, and immune modulation via interaction with its cognate receptor, the neurokinin 1 receptor (NK1-R), is produced by monocyte/macrophages. While the presence of NK1-R on neurons is well known, its role on cells of the immune system such as monocyte/macrophages is just beginning to emerge. Therefore, we have examined the expression of SP and NK1-R and their relationship to SIV/HIV encephalitis (SIVE/HIVE) lesions and SIV-infected cells. These studies demonstrated intense expression of SP and NK1-R in SIVE lesions, with macrophages being the principal cell expressing NK1-R. Interestingly, all of the SIV-infected macrophages expressed NK1-R. Additionally, we examined the functional role of SP as a proinflammatory mediator of monocyte activation and chemotaxis. These studies demonstrated that treatment of monocytes with SP elicited changes in cell-surface expression for CCR5 and NK1-R in a dose-dependent manner. Moreover, pretreatment with SP enhanced both SP- and CCL5-mediated chemotaxis. All of these findings suggest that SP and NK1-R are important in SIV infection of macrophages and the development of SIVE lesions.The neuropathogenesis of HIV infection is complex and has led to the development of nonhuman primate models using infection of macaques with the simian immunodeficiency virus (SIV). The human and simian immunodeficiency viruses are closely related and produce nearly identical conditions in their respective hosts, thus the rhesus macaque infected with SIV is the premier animal model for the study of AIDS pathogenesis in general and of the neuropathogenesis of AIDS in particular. Additionally, nonhuman primates are widely used in neuroscience research, including neurophysiologic and neurobehavioral studies. Recent studies suggest a link between psychiatric disorders like stress and depression and the neuropathogenesis of HIV and/or its progression to AIDS.1,2 Neuroinvasion by SIV and HIV occurs early in infection at the time of peak viremia. The virus most likely enters the brain within cells of monocyte/macrophage lineage, and the perivascular macrophage is the primary cell type productively infected within the CNS.3,4Approximately 25 to 30% of untreated HIV-infected adult humans develop a debilitating neurological disorder termed AIDS dementia complex (ADC).5,6,7 A wide variety of cytokines, which include IL-1beta, IL-6, and TNF-α, chemokines (CCL2, CCL3, CCL4 and CCL5), adhesion molecules, and other molecules such as Substance P (SP) produced by different cell types have been implicated in this process.1,4,8,9 Microscopic evaluation of brains from individuals with ADC reveals a broad spectrum of pathological features including neuronal changes, multifocal encephalitis, accumulation of inflammatory macrophages and multinucleated giant cells (MNGCs), cerebral cortical atrophy, and white matter pallor.5,10 The histopathological substrate of ADC, referred to as HIV encephalitis (HIVE), is characterized by perivascular accumulation of macrophages and MNGCs in the CNS with abundant infection of brain macrophages.4,11 In addition to the pathological manifestations within the brains of individuals with ADC, extensive neurobehavioral effects have been characterized and include impaired fine motor control and memory, altered emotional control, motor slowing, and possibly depression. Compelling data from recent studies reveal the significance of inflammatory mediators including the neuropeptide SP in the neuropathogenesis of AIDS12,13,14 as well as in clinical neurobehavioral effects of depression.2,3,4 Such findings suggest that SP participates in important aspects of immune-neural communication and likely contributes to immune modulation in HIV/SIV infection.SP is an 11-aa neuropeptide and is the most extensively studied and most abundant member of the tachykinin family. SP is synthesized mainly by primary sensory neurons, however recent studies have demonstrated that immune cells also express SP mRNA and protein during SIV/HIV-infection,1,8 suggesting that it may contribute to neurological disease by acting on its preferred receptor, NK1-R, a G-protein–coupled receptor expressed on T-cells, B-cells, monocyte/macrophages, NK cells, astrocytes, and neurons.9 Activation of NK1-R by SP results in increased phagocytic response in macrophages, enhanced inflammatory cytokine production by immune cells, and possible induction of a chemotactic response in monocyte macrophages, thus facilitating immune cell trafficking at sites of inflammation or infection.16,17,18,19,20 SP has a role in AIDS, and results from recent in vivo studies1,8,15,21,22 revealed that NK1-R antagonists have an antiviral effect,23 likely through down-regulation of CCR59 as well as immunomodulatory and antidepressive effects.23,24 The major focus of existing work on SP (and its receptor-NK1-R) in macaques, however, has focused on its role as a neurotransmitter or neuromodulator and therefore the distribution of SP and NK1-R on neurons is well known, while little data exists on the in vivo distribution of SP and NK1-R on other cell types.Because the cellular expression of SP and its receptor NK1-R is not fully characterized in normal or SIV-infected macaques, we examined the cellular distribution/location and phenotype of SP and NK1-R expressing cells in the CNS in vitro and in vivo using multiple techniques and at various stages of infection in animals with or without SIVE. Such analysis allowed us to assess spatial correlations between the presence of SIV-infected cells and cells positive for SP and NK1-R. Additionally, we examined the functional aspects of SP/NK1-R signaling in monocyte activation and chemotaxis. Data from our immunofluorescence and in situ hybridization studies show that while NK1-R is expressed in astrocytes and neurons, it is intensely expressed in SIVE lesions. NK1-R expression was detected in all SIV-infected cells associated with SIVE lesions, of which macrophages were the predominant cell type and also the primary cell type expressing NK1-R. T-cells were found in small numbers in SIVE lesions and were rarely infected but were shown to express NK1-R when present. Our quantitative flow cytometric analysis demonstrates that SP functionally regulates NK1-R and CCR5 expression on macaque monocytes. Furthermore, pretreatment of monocytes with SP enhanced SP-mediated chemotaxis as well as CCL5-mediated chemotaxis. The enhancement of SP-mediated chemotaxis in the presence of CCL5 demonstrates cross talk between NK1-R and CCR5 signaling pathways. These findings suggest that SP contributes to SIV-associated neurological disease and suggest that SP also has a role in augmented cellular trafficking across the blood-brain barrier and thus the development of SIVE lesions. This insight into the function of SP and NK1-R allows for a better understanding of the interaction between the immune and nervous systems, and may lead to advancements in treatment of neurological and neuropsychiatric disease.  相似文献   
58.
Summary The ascomycete fungus Ascochyta rabiei, an important pathogen of the grain legume crop chickpea (Cicer arietinum L.) in the Mediterranean region, has not been adequately characterized in molecular terms. We therefore used DNA fingerprinting, with synthetic oligodeoxynucleotides complementary to simple repetitive sequences, to pathotype different isolates of the fungus. Six single-spored A. rabiei isolates were first categorized using a host differential set of nine chickpea genotypes. Seedlings were inoculated under controlled environmental conditions, and disease severity was recorded 9 days after inoculation. DNA was extracted from in vitro-grown mycelia of the six purified fungal isolates, restricted with EcoRI, HinfI, MboII and TaqI, and fingerprinted with radiolabeled (GATA)4, (GTG)5, (CA)8, and (TCC)5, respectively. High levels of polymorphism were detected with optimal enzyme/probe combinations that allow one to discriminate between the isolates. The potential of DNA fingerprinting with simple repetitive sequences can thus be expanded to the identification of fungal races and pathotypes. The characterization of the geographic distribution and genetic variability of pathotypes will facilitate the selection of suitable host cultivars to be grown in specific regions.  相似文献   
59.

Study Objective

To determine the diagnosis, management, and outcome for children and adolescents with borderline ovarian tumor (BOT), and to provide a review of the literature on BOT in children and adolescents.

Design

A retrospective cohort study of female adolescents younger than age 21 years diagnosed with BOT between January 2001 and May 2016.

Setting

Texas Children's Hospital, Houston, Texas.

Participants

Fourteen patients (ages 12 to 18 years) diagnosed with BOT.

Main Outcome Measures

Clinical presentation, preoperative characteristics, surgical technique, cancer stage, histology, treatment, and recurrence.

Results

Median age at diagnosis was 15.5 years, with most postmenarchal. Abdominal mass/pain were the most common presenting symptoms. Median tumor size was 16.6 cm (range, 4-32 cm). Preoperative cancer antigen 125 (CA 125) was elevated in 54% (7/13) of cases. All patients had fertility-preserving surgery, either cystectomy (CY) or unilateral salpingo-oophorectomy (USO): 5 via laparoscopy (LSC) and 9 via laparotomy. Most were stage I with 5 serous and 9 mucinous BOT histology. No one received adjuvant chemotherapy. Two patients had recurrence. One had ipsilateral recurrence 2 months after LSC CY for FIGO stage IC1 mucinous BOT. The second had contralateral recurrence 15 months after laparotomy, right USO for FIGO stage IIIC serous BOT treated with LSC CY, then a second recurrence treated with USO after oocyte cryopreservation for fertility preservation. All patients were alive at last follow-up, 1 with disease.

Conclusions

BOT in children and adolescents can be treated conservatively with fertility-preserving techniques and surveillance with good outcome. The role of adjuvant therapy is not known.  相似文献   
60.
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