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1.
Brucellosis is a world prevalent endemic illness that is transmitted from domestic animals to humans. Brucella spp. exploits urease for survival in the harsh conditions of stomach during the gastrointestinal infection. In this study, we examined the immune response and the protection elicited by using recombinant Brucella urease (rUrease) vaccination in BALB/c mice. The urease gene was cloned in pET28a and the resulting recombinant protein was employed as subunit vaccine. Recombinant protein was administered subcutaneously and intraperitoneally. Dosage reduction was observed with subcutaneous (SC) vaccination when compared with intraperitoneal (IP) vaccination. rUrease induced mixed Th1–Th2 immune responses with high titers of specific IgG1 and IgG2a. In lymphocyte proliferation assay, splenocytes from IP and SC‐vaccinated mice displayed a strong recall proliferative response with high amounts of IL‐4, IL‐12 and IFN‐γ production. Vaccinated mice were challenged with virulent Brucella melitensis, B. abortus and B. suis. The SC vaccination route exhibited a higher degree of protection than IP vaccination (p value ≤ 0.05). Altogether, our results indicated that rUrease could be a useful antigen candidate for the development of subunit vaccines against brucellosis.  相似文献   
2.
Doxorubicin (DOX) is the most commonly used anticancer drug; however, it has limited use because prolonged administration may result in severe cardiotoxicity. Simvastatin (SIM), generally prescribed for hypercholesterolaemia, has also shown salubrious results in the monotherapy or combinational drug therapy of different cancers in various models. Nanoparticle drug delivery systems are a novel way of improving therapeutics and also improving the absorption and specificity of drugs towards tumour cells. In this study, we exploited this technology to increase drug specificity and minimize imminent adverse effects. In this study, the antitumour activity of the combination formulas of DOX and SIM, either loaded in water (DOX‐SIM‐Solution) or nanoemulsions (NEs) (DOX‐SIM‐NE), was evaluated in a Swiss albino mouse model of Ehrlich ascites carcinoma. The anticancer effect was assessed by quantifying the change in body weight, mean survival time, and percent increase in lifespan (%ILS), determining haematological and serum biochemical parameters (liver function test, kidney function test and lipid profile parameters) as well as studying the histopathological alterations in liver tissues. We observed a clear increase in %ILS of the DOX‐SIM‐Solution group (265.30) that was double the %ILS of the DOX‐SIM‐NE group (134.70). However, DOX‐SIM‐NE had a non‐toxic effect on the haematological parameters, whereas DOX‐SIM‐Solution increased the levels of haemoglobin and lymphocytes. Furthermore, the encapsulation of SIM and DOX into NEs improved the levels of all serum biochemical parameters compared to the DOX‐SIM‐Solution. A reduction in the side effects of DOX‐SIM‐NE on the liver was also established using light microscopy, which revealed that the morphologies of the hepatocytes of the mice were less affected by administration of the DOX‐SIM‐NE treatment than with the DOX‐SIM‐Solution treatment. The study showed that incorporating SIM into the DOX‐loaded‐NE formulation remarkably improved its efficiency and simultaneously reduced its adverse effects.  相似文献   
3.
The floating metacarpal bone is a result of simultaneous fracture-dislocation of both carpometacarpal and metacarpophalangeal joints. This rare entity may be associated with other hand injuries. Here we present a floating index metacarpal with concomitant 3rd–5th carpometacarpal fracture-dislocations. Excellent functional short-term result was achieved after open metacarpopha langeal reduction and closed carpometacarpal reduction and percutaneous pinning.  相似文献   
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The World Health Organization has reported an annual global suicide rate of 14.5 per 100,000 people. On the other hand, it is estimated that approximately one‐third of the global population are infected with Toxoplasma gondii (T. gondii) parasite. It is widely assumed that microbial pathogens, such as T. gondii, are probably associated with affective and behavioural modulation. The present article aimed to assess the proposed role of toxoplasmosis in raising the risk of suicidal ideation (SI) and suicide attempts (SA) using the available epidemiological data. Seven major electronic databases and the Internet search engine Google were searched for all the studies published between the 1st of January 1950 and 31st of October 2019. The heterogeneity and the risk of bias within and across studies were assessed. Following data extraction, pooled odds ratios (ORs) with 95% confidence interval (CI) across studies were calculated using the random‐effects models. A total number of 9,696 articles were screened and 27 studies were regarded as eligible in our systematic review (SI with five papers and 22 papers on SA). A significant association was detected between antibodies against T. gondii with TA (ORs = 1.57; 95% confidence interval [CI] 1.23–2.00, p = .000). Exploration of the association between T. gondii and SA yielded a positive effect of seropositivity for IgG antibodies but not IgM. Despite the limited number of studies, a statistical association was detected between suicidal behaviours and infection with latent T. gondii.  相似文献   
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7.
Ruggieri  PM; Laub  GA; Masaryk  TJ; Modic  MT 《Radiology》1989,171(3):785-791
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.  相似文献   
8.
OBJECTIVES: To characterise mycobacterial clinical isolates based on amplification of the rpoB gene. SETTING: One hundred and thirty-five mycobacterial isolates cultured from suspected pulmonary tuberculosis (TB) patients were identified phenotypically. Molecular characterisation of the isolates was performed based on amplification of the rpoB gene, using duplex polymerase chain reaction (DPCR), PCR-restriction fragment length polymorphism (RFLP) and nested PCR-based sequence analysis techniques. RESULTS: The DPCR assay identified 129 of 135 (95.5%) clinical isolates as Mycobacterium tuberculosis complex species. Restriction enzyme analysis of the rpoB PCR product using Hind II identified 134 of the 135 (99.3%) isolates as M. tuberculosis complex, while nested PCR sequence analysis of the rpoB gene identified 133/133 examined isolates (100%) as M. tuberculosis species. No mycobacteria other than M. tuberculosis (MOTT) were detected among the studied isolates. CONCLUSION: DPCR, PCR/RFLP Hind II and nested PCR sequence analysis of the rpoB gene techniques showed comparable efficiency in the characterisation of Mycobacterium isolates. Nested PCR sequence analysis of the rpoB gene was superior to PCR/RFLP for characterisation of suspected M. tuberculosis isolates, while the DPCR technique showed less sensitivity. As PCR-RFLP requires less sophisticated laboratory facilities than nested PCR sequence analysis, it would be more appropriate to be adopted for accurate characterisation of mycobacteria in countries with a weak infrastructure.  相似文献   
9.
In cases of cerebrospinal fluid (CSF) rhinorrhea following lateral skull base surgery, fibrosis and fibrin formation resulting from meningitis has been postulated as a mechanism of spontaneously resolving the CSF leak. This study was undertaken to explore any possible relationship between the cessation of CSF leak and meningitis. A retrospective study at a tertiary referral center of 232 consecutive patients was performed. Out of a total of 232 procedures, 29 patients developed CSF rhinorrhea, of whom 7 subsequently developed meningitis. Bacteria were isolated in CSF obtained at lumbar puncture in 5 cases, with the CSF analysis in the remaining 2 cases suggesting aseptic meningitis. Conservative treatment failed to stop the CSF rhinorrhea in 6 of 7 cases. In this study, the development of meningitis did not appear to aid in the resolution of the CSF rhinorrhea. We conclude that surgical intervention should not be delayed in the expectation that meningitis and conservative interventions may promote CSF leak resolution.  相似文献   
10.
BACKGROUND: Intravenous methylprednisolone pulses (IVMP) are more efficacious and better tolerated than oral prednisone in Graves' ophthalmopathy (GO) patients. However, acute and severe liver damage has been reported in sporadic cases during IVMP, resulting in fatal acute liver failure in four patients so far. The mechanism causing the liver damage is incompletely understood. DESIGN: We performed a prospective observational study in 13 patients with dysthyroid optic neuropathy (group A) and in 14 patients with moderately severe GO (group B) who were treated with high-dose (group A) or low-dose (group B) IVMP; cumulative steroid doses were 8.45 g in group A and 4.5 g in group B, and follow-up time was 24 weeks. MAIN OUTCOME: Slight increases in serum aminotransferases (in alanine aminotransferase [ALAT] more than in aspartate aminotransferase [ASAT]) were observed, in seven patients exceeding the upper normal limit of 40 U/L. These changes were more prominent in group A than in group B as was also evident from a decrease in ASAT/ALAT ratio in group A but not in group B. Changes in serum aminotransferases occurred especially in the first 6 weeks of IVMP, becoming smaller thereafter with the decrease in steroid dosage. Pretreatment liver steatosis or diabetes were not related to liver damage, but preexistent viral hepatitis was. CONCLUSION: IVMP in GO patients causes dose-dependent liver damage by a direct toxic effect of glucocorticoids on hepatocytes. Nevertheless, IVMP seems to be pretty safe if cumulative doses exceeding 8 g are avoided and liver function is checked before and at regular intervals during pulse therapy.  相似文献   
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