Asthma: recent advances

Asthma represents an increasing source of morbility and significant mortality in westernized societies. A recent meeting discussed progress in understanding the genetic, molecular and immunological basis of this allergic disorder.     

Preparation and evaluation of poly(L-lactide-co-glycolide) (PLGA) microbubbles as a contrast agent for myocardial contrast echocardiography

A kind of absorbable PLGA microbubble-based contrast agent (PLGA microspheres with porous or hollow inner structure) was fabricated by an improved double emulsion-solvent evaporation method. The contrast efficiency was evaluated and proved both in vitro and in vivo. By adjusting the polymer concentration and volume of the inner aqueous phase during the fabrication of microbubbles, the inner structure of the microbubbles could be controlled. Both air-filled and perfluoropropane-filled microbubbles can opacify the left ventricle. However, when compared with air-filled microbubbles, perfluoropropane-filled microbubbles can produce significantly longer enhancement in left ventricle in the dog model due to the lower diffusivity and lower solubility of perfluoropropane in blood. A suspension of perfluoropropane-filled PLGA microbubbles (1.8 microm average microbubbles size, 2 x 10(8) microbubbles/mL concentration) has successfully and safely achieved myocardial opacification in closed-chest dogs. A perfusion defect was observed in both of the two dogs with acute myocardial infarction with Power Contrast Imaging (PCI) triggered technology. In the examination of contrast in both ventricular and myocardial opacification, the high mechanical index (MI) was found to have superior contrast sensitivity over the low MI for PLGA-based contrast agents.     

超声二次谐波声面声学造影评价冠脉的微血管血流灌注

目的：本文获取冠状动脉血流变化所致的心肌灌注类型,以了解冠脉的微血管血流灌注变化。方法：36人先后完成冠状动脉影,静脉注射声学造影剂利声显（Levovist),通过超声二次谐波技术获取心肌灌注图像,按心肌灌注积分指数将病人分为三组。结果：三组病人的冠状动脉狭窄程度、心肌灌注积分指数明显差异（P＜0．001）,冠状动脉狭窄波＜75％者,病人心肌灌注多为正常,随着冠状动脉狭窄程度加重,出现不同程度的心肌灌注异常。8例完全阻塞的冠状动脉有不同的冠状动脉侧支循环表现为不同的心肌灌注类型。结论：静脉心肌声学造影是反映心肌灌注的有效方法,能够反应冠状动脉血流的改变及微循环结构的完整性变化,从而弥补冠状动脉造影仅能显示心外膜下的冠状动脉而无法观察毛细血管水平的心肌灌注之缺限。当心肌灌注不良时,MCE能提示冠状动脉病变的存在,及其严重性,但要注意侧支循环对心肌灌注之影响,可影响对冠脉病变程度判断的精确性。冠状动脉造影确定某支冠脉病变时,MCE心机灌注有助于评价侧支循环状态。     

心肌超声造影心动图对高强度聚焦超声左心室心肌消融心肌坏死范围的评价

目的探讨心肌超声造影心动图评价高强度聚焦超声（HIFU）左心室心肌消融心肌坏死范围的可行性。方法新西兰兔9只,兔龄8～12个月,体质量（3.0±0.2）kg（2.8～3.5 kg）。HIFU治疗频率1.5 MHz,强度9.64 kW/cm2,脉冲照射方式,Ton=0.2 s、0.3 s,Toff=1.0 s、1.5 s,重复次数20次,靶区范围3 mm×2 mm。照射后行左心室心肌超声造影心动图,然后取下心脏,做2mm心肌切片,用2,3,5-三苯基氯化四氮唑（TTC）染色。测量造影剂充盈缺损面积及与之相对应心肌切片TTC染色心肌坏死面积,并计算其占整个心肌的面积百分比。结果造影剂充盈缺损面积百分比（13.7%±6.7%）与TTC染色心肌坏死面积百分比（15.5%±4.9%）间差异无统计学意义（P〉0.05）;两者间呈显著相关（r=0.94,P〈0.05）。结论心肌超声造影心动图可用于评价HIFU左心室心肌消融心肌坏死范围。     

Glomerular pathology: recent advances

The last decade has seen significant advances in the fields of cellular and molecular biology and pathology. These have contributed to our understanding of the mechanisms of glomerular disease and indicate possible novel approaches to therapy. This review discusses recent insights into the pathogenesis of glomerular disease, with consideration of the roles of intrinsic glomerular cells, infiltrating inflammatory cells, circulating permeability factors, and antibodies, and recent advances in the molecular pathology of the glomerular basement membrane. Changes in the perception of some well-established glomerular entities such as focal segmental glomerulosclerosis are considered. In addition, a number of newly-recognized specific glomerulopathies including collapsing glomerulopathy, fibrillary and immunotactoid glomerulopathy, fibronectin glomerulopathy, and collagenofibrotic glomerulopathy are briefly reviewed. © 1998 John Wiley & Sons, Ltd.     

Uterine mesenchymal tumours: recent advances

Almost all uterine mesenchymal tumours have been historically classified as either smooth muscle or endometrial stromal neoplasms. Recent application of molecular techniques has identified numerous lesions with distinctive genetic abnormalities and clinicopathological characteristics. Newly discovered uterine sarcoma subtypes include high-grade endometrial stromal sarcomas with BCOR genetic abnormalities, fibrosarcoma-like uterine sarcomas with NTRK rearrangements and COL1A–PDGFRB fusions, as well as undifferentiated uterine sarcomas with SMARCA4 mutations. Novel PLAG1 and PGR fusions have been identified in subsets of myxoid and epithelioid leiomyosarcomas. Some uterine tumours resembling ovarian sex-cord tumour harbour GREB1 and ESR1 rearrangements. Histological and immunophenotypical features as well as underlying genetic abnormalities defining these lesions are discussed.     

Biochemistry of rickettsiae: recent advances

The application of new biotechnology to the study of the biochemistry of rickettsiae was a prominent feature of the presentations at the 3rd International Symposium on Rickettsiae and Rickettsial Diseases, held in Smolenice near Bratislava in September 1984. This review is an attempt to summarize recent advances leading up to these presentations as well as the studies that have been reported in the two years since the meeting. Since rickettsiae are intracellular parasites, most reviews deal with the interaction of rickettsiae with host cells. It is useful, however, to focus also--as we have done--on the properties of rickettsiae that can be demonstrated in the absence of their hosts, although, undoubtedly, many of these properties reflect adaptation to an intracellular microenvironment.     

Autism: recent molecular genetic advances

Autism (MIM 209850) is a severe neuropsychiatric disorder of unknown aetiology with profound consequences for patients and their families. Strong evidence from twin and family studies indicates the importance of genetic factors in the development of idiopathic autism, although it is clear that these influences are complex. This review focuses on recent molecular investigations to identify susceptibility loci implicated in autistic disorder.     

Diagnosis of interatrial shunts using contrast echocardiography

M-mode contrast echocardiography with peripheral venous injections was performed in 73 patients with interatrial communications: 48 (group 1) had a hemodynamically significant atrial septal defect (ASD), 19 (group 2) had a patent foramen ovale (PFO) without clinical or oxymetric evidence of a shunt. The remaining 6 (group 3) had an interatrial communication in combination with severe additional congenital malformations predisposing to a right to left (R-L) shunt. Contrast studies were considered positive for a shunt lesion when at least five clearly recognizable contrast echoes appeared in the left heart following one injection. During quiet respiration positive contrast studies were obtained in 85% of all ASD patients (including all 10 with Eisenmenger's reaction and 31/38 [82%] uncomplicated cases); in 37% of the PFO cases (including 3/13 with normal right heart pressures), and in 53/73 (73%) of all patients with interatrial communications. The intensity of contrast shunting was variable in all groups. Opacification of the mitral funnel (which is typical for an atrial level shunt) was observed in 45 patients. In 8 patients with positive studies the few contrast echoes, that appeared in the left heart were first seen after they had left the mitral valve. Contrast injections into the pulmonary artery were performed in a control group of 29 patients. No contrast appeared in the left heart as expected. In 57 patients (39 ASD, 17 PFO, 1 group 3) contrast studies were also performed during the Valsalva maneuver. Valsalva provocation resulted in increased contrast shunting in 19, led to new mitral funnel opacification in 9 and improved the sensitivity of contrast echocardiography by 9 and 26% in ASD and PFO cases respectively. The intensity of contrast shunting was largely independent of the hemodynamic findings and was often variable upon subsequent injections in the same patient. Therefore contrast echocardiography is not helpful in predicting the L-R shunt or the pulmonary artery pressure and does not seem suited for follow-up studies. The differentiation between true contrast echoes in the left heart and artifacts, noise echoes, "overload", or incomplete mitral structures and the differentiation between interatrial and interventricular contrast shunting is usually easy. However the distinction between a hemodynamically significant ASD and pulmonary arteriovenous fistulas, certain venous anomalies or a patent foramen ovale may be difficult or even impossible by contrast echocardiographic criteria alone. Resting two-dimensional contrast echocardiograms were recorded in 57 patients including 34 with ASD, 18 with PFO and 5 from group 3.(ABSTRACT TRUNCATED AT 400 WORDS)     

Control of endemic methicillin-resistant Staphylococcus aureus—recent advances and future challenges

Although the exact burden of disease caused by methicillin-resistant Staphylococcus aureus (MRSA) remains largely unknown, most experts agree that MRSA infections are an important clinical and public health problem. Thousands of reports have been published during the last four decades concerning epidemiological and microbiological aspects of MRSA, but uncertainty remains about the best approach to prevent and control this worldwide plague, especially endemic MRSA. Epidemiological methods, e.g., risk scores for targeted screening upon admission, rapid molecular tests and pre-emptive isolation of high-risk patients, new decontamination regimens and restriction of certain antibiotic classes, are all promising approaches that may decrease MRSA cross-transmission; however, further evidence is needed before these strategies can be implemented on a wide scale. Control of community MRSA is an additional challenge for the future, requiring improved surveillance and contact tracing, as well as education and treatment of both infected cases and colonised contacts. This review summarises recent advances and studies that address these issues. Overall, it seems that there is no level of MRSA prevalence for which active control measures are no longer warranted.     

造影超声心动图在心脏肿瘤诊断中的应用价值

心脏肿瘤的临床诊断、治疗决策和预后判断高度依赖超声心动图等影像学检查.常规超声心动图对心脏肿瘤与心脏非肿瘤性占位病变的鉴别以及对心脏肿瘤的良、恶性鉴别能力有限.造影超声心动图利用微气泡进行血流示踪,能使心脏占位显示得更为清晰,提高了超声对心脏肿瘤的诊断准确率;心肌声学造影技术(MCE)还能观察占位内部的血供情况,从而有助于定性诊断心脏肿瘤的良恶性,有重要的临床应用价值.     

Peyronie's disease: Review and recent advances

Peyronie's disease is an incurable, sexually debilitating fibrotic disease of the penis that results in penile curvature, coital failure, and significant psychological stress for patients and their partners. Appropriate treatment should be individualized and tailored to the patient's goals and expectations, disease history, physical exam findings, and erectile function. While medical treatments exist, there is little evidence to support their use. High-quality data supporting more recent advances in injectable therapies, interferon α-2b and collagenase clostridium histolyticum, show great promise for their application. Once the disease has stabilized, surgical correction is also an excellent option for patients with significant Peyronie's disease accompanied by functional impairment. Outcomes are satisfactory when proper treatment decisions are made, with the goal being expected return to normal sexual function following treatment.     

Classical and recent advances in the treatment of inflammatory bowel diseases

Crohn''s disease (CD) and ulcerative colitis (UC) are intestinal disorders that comprise the inflammatory bowel diseases (IBD). These disorders have a significant effect on the quality of life of affected patients and the increasing number of IBD cases worldwide is a growing concern. Because of the overall burden of IBD and its multifactorial etiology, efforts have been made to improve the medical management of these inflammatory conditions. The classical therapeutic strategies aim to control the exacerbated host immune response with aminosalicylates, antibiotics, corticosteroids, thiopurines, methotrexate and anti-tumor necrosis factor (TNF) biological agents. Although successful in the treatment of several CD or UC conditions, these drugs have limited effectiveness, and variable responses may culminate in unpredictable outcomes. The ideal therapy should reduce inflammation without inducing immunosuppression, and remains a challenge to health care personnel. Recently, a number of additional approaches to IBD therapy, such as new target molecules for biological agents and cellular therapy, have shown promising results. A deeper understanding of IBD pathogenesis and the availability of novel therapies are needed to improve therapeutic success. This review describes the overall key features of therapies currently employed in clinical practice as well as novel and future alternative IBD treatment methods.