细菌L型与人乳头状瘤病毒致凹空细胞的比较

应用组织切片革兰染色和免疫组织化学染色等方法,对２４０例有凹空细胞的标本（鳞状细胞乳头状瘤３６例．尖锐湿疣６１例,喉癌８５例,子宫颈鳞癌５８例）进行人乳头状瘤病毒（ＨＰＶ）和细菌Ｌ型检测,比较两者在组织中的检出阳性率、分布及组织病理学表现。结果发现,凹空细胞中ＨＰＶ—Ａｇ检出阳性率（７２．１％）与金葡菌ＣｏｗａｎＩ株Ｌ型－Ａｇ检出阳性率（６５．０％）无显著性差异（Ｐ＞０．０５）;革兰染色有６５．４％的凹空细胞检出Ｌ型菌,ＨＰＶ－Ａｇ与Ｌ型－Ａｇ在组织中的分布和组织病理学表现基本一致。表明细菌Ｌ型与病毒具有相似的病理致病特征。细菌Ｌ型感染是引发上述病变及凹空细胞的重要原因之一。     

流式细胞仪检测纳帕海高原湿地浮游病毒和浮游细菌丰度

【背景】浮游病毒是水体微生物群落中重要的组成成分,深入研究浮游病毒的时空分布有助于更好地保护和开发当地的微生物资源。【目的】对采集到的纳帕海高原湿地水样中的浮游病毒和浮游细菌进行计数,揭示纳帕海高原湿地浮游病毒的分布规律。【方法】采用流式细胞仪检测2013年12月和2014年9月纳帕海高原湿地7个水样的浮游病毒与浮游细菌丰度,并对影响浮游病毒丰度的因素,如细菌丰度、叶绿素a含量以及其他环境因子进行了相关性分析。【结果】季节分布上,雨季浮游病毒和浮游细菌丰度高于旱季;水平分布上,原水样品的浮游病毒高于湿地水和淤泥水。旱季水样的浮游病毒丰度受到细菌丰度及叶绿素a浓度的影响较大;雨季水样的浮游病毒丰度受到水体的p H值和温度的影响较大。【结论】纳帕海高原湿地的浮游病毒和浮游细菌是比较活跃的。浮游病毒丰度在不同季节、不同采样点受到细菌丰度和叶绿素a浓度等因素的不同影响。在旱季噬菌体而非噬藻体或浮游植物病毒是纳帕海高原湿地中浮游病毒的优势种群。     

纳帕海高原湿地浮游病毒丰度及其与可溶性有机碳关系

【背景】浮游病毒在有机碳循环中具有重要作用。【目的】研究纳帕海高原湿地不同季节水样及土样中的浮游病毒和细菌丰度,并分析不同季节浮游病毒丰度与可溶性有机碳的关系。【方法】利用荧光显微镜技术检测不同季节水样中浮游病毒和细菌丰度,利用流式细胞仪技术检测不同季节土壤样品中病毒颗粒和细菌丰度。【结果】雨季所有样品浮游细菌和浮游病毒丰度分别为3.38×10~6/mL和4.38×10~7/mL,旱季所有样品的浮游细菌和浮游病毒丰度分别为8.85×10~5/mL和9.66×10~6/mL,浮游细菌和浮游病毒丰度年平均值分别为2.13×10~6/mL和2.67×10~7/mL。不同季节浮游细菌和浮游病毒的丰度有显著性差异,雨季明显高于旱季(P0.01)。雨季细菌碳产量为8.01μg C/(L·h),旱季为10.30μg C/(L·h)。雨季浮游病毒裂解细菌贡献的可溶性有机碳(Dissolved organic carbon,DOC)占总DOC库的32.38%-76.38%,而旱季为8.23%-47.87%。【结论】浮游病毒在纳帕海高原湿地有机碳循环中具有重要作用。     

巨噬细胞集落刺激因子用于治疗感染性疾病的探讨

巨噬细胞集落刺激因子（Ｍ－ＣＳＦ）对机体感染性疾病的发生、发展有重要影响。已经在体内外证实Ｍ－ＣＳＦ对某些细菌、真菌和病毒有抗感染作用，有潜在的临床应用价值；但在某些情况下也能加重某些感染性疾病的病情。     

超抗原及其临床意义

超抗原是细菌和病毒的产物,它的一个显著生物学特征是能非特异地刺激Ｔ细胞增殖,并促进其释放ＴＮＦ、ＩＦＮ－γ、ＩＬ－２等细胞因子。它激活Ｔ细胞的机制与普通抗原和Ｔ细胞有发裂原有显著不同。微生物超抗原的生物学特征与这些微生物所致疾病的发病机制密切相关。     

土壤含水量驱动土壤病毒和细菌多度及其与土壤异养呼吸关系的变化

土壤微生物是维持陆地生态系统稳定性和功能的重要组成部分。病毒是地球上数量最多的生物实体,也是若干类型生境中微生物数量的重要调节者。因此,了解病毒与微生物的相互作用,对深入认识包括碳循环在内的生态系统过程具有重要意义。在实验室建立土壤微宇宙实验系统,跟踪调查恒定低含水量、恒定高含水量和波动含水量3种水分处理下土壤病毒和细菌多度的变化,以及土壤异养呼吸速率对土壤病毒-细菌相互作用的响应。相较于低水分处理,高水分处理显著增加了病毒多度（P<0.001）和病毒-细菌多度比（P=0.0026）,波动水分处理显著增加了病毒多度（P<0.001）。在高水分处理的土壤微宇宙中,细菌和病毒多度呈现出随时间动荡的信号,即细菌多度表现出增加-降低-增加的趋势,而病毒多度则表现出增加-降低的趋势,且其变化滞后于细菌。土壤异养呼吸速率与土壤含水量（P<0.001）、细菌多度（P=0.0045）和病毒多度（P<0.001）都具有显著的正相关关系。这些结果说明：病毒导致的下行控制可能是细菌多度的重要影响因子,在水分增加情形下,病毒有可能通过加速细菌的更新速率进而加速土壤呼吸。因此,病毒与细菌的相互作用可能是碳循环的重要决定因素。     

90株肠杆菌属细菌诱导型β-内酰胺酶的检测与药敏结果

目的：了解肠杆菌属细菌诱导型β－内酰胺酶及药敏情况。方法：应用双纸片扩散法－分别采用亚胺培南和头孢西丁两种诱导剂以及头孢他啶和头孢噻肟两种目标物－测定90株肠杆菌属细菌的诱导型β－内酰胺酶,并用VITEK32－AMS测定该90株细菌对14种抗生素的耐药性。结果：亚胺培南组和头孢西丁组分别有51株和25株细菌产生诱导型β－内酰胺酶,头孢他啶组和头孢噻肟组分别有50株和30株细菌的诱导型β－内酰胺酶阳性,以头孢西丁,头孢噻吩,氨苄西林的耐药率最高,亚胺培南的耐药率最低。结论：亚胺培南优于头孢西丁,头孢他啶优于头孢噻肟,51株产酶组与39株非产酶组细菌的耐药差异无显著性。临床用药时应注意亚胺培南的高诱导性和体外药敏试验的局限性,提倡微生物实验室注重诱导型β－内酰胺酶的测定。     

柠檬提取物抑菌、杀灭病毒作用机制研究

目的观察柠檬提取物对细菌生物膜的消除作用,对柠檬提取物抑制多重耐药金黄色葡萄球菌的机制进行初步研究,以及对环境中富集的病毒消除作用的研究。方法采用高分子滤膜法制备金黄色葡萄球菌生物膜后,加入柠檬提取物分别作用1、2和3h,通过细菌菌落计数判定不同生物膜的细菌存活数;采用SDS—PAGE电泳法,观察在柠檬提取物作用下菌体蛋白质的变化;EcoRⅠ酶切金黄色葡萄球菌DNA,观察酶切图谱的改变;在低渗环境下动态观察柠檬提取物在不同作用时间对细菌细胞壁的影响;通过柠檬提取物对病毒作用后RNA量的变化,说明柠檬提取物具有杀灭病毒的作用。结果柠檬提取物对生物膜中的细菌具有杀菌作用,且随作用时间的延长而逐渐增强;柠檬提取物对细菌蛋白质的组成和表达量均有一定影响,同时细菌DNA的EcoRⅠ酶切图谱发生改变;柠檬提取物作用15min时细菌呈现明显的胞壁缺损现象,即细菌个体胀大,呈现大球形;经柠檬提取物作用后,RNA病毒被杀灭。结论结果显示柠檬提取物对耐药金黄色葡萄球菌所形成的生物膜具有明显抑制作用;在柠檬提取物作用下,菌体蛋白合成量发生改变,同时对细菌的DNA和细胞壁有明显的影响。柠檬提取物处理病毒悬液后,病毒RNA量显著减少,说明病毒RNA结构被破坏。     

Sindbis病毒蚀斑方法的建立及其在血液制品病毒灭活实验中的应用

实验建立了Ｓｉｎｄｂｉｓ病毒在ＢＨＫ－２１细胞内蚀斑形成的方法,Ｓｉｎｄｂｉｓ病毒接种于ＢＨＫ－２１细胞内,３天半染色,结果显示蚀斑清晰可见,直径为２－４ｍｍ,病毒滴度已达高峰期,同时将此方法用于血液制品病毒灭活实验中,结果表明该方法准确、客观,Ｓｉｎｄｂｉｓ病毒在Ｓ／Ｄ低ｐＨ孵放法等灭活病毒实验中作为有脂质包膜类病毒的指示病毒具有相对稳定性,较为适宜并且能客观的体现出各种灭活方法灭活病毒的作用     

贵州高原湖泊细菌和病毒分布特征及影响因素

应用SYBR Green Ⅰ荧光显微镜计数法,研究了贵州阿哈湖和百花湖细菌和病毒丰度的垂直分布特征,探讨了它们与温度、pH、溶解氧(DO)、电导率和溶解有机碳(DOC)之间的关系.两湖DOC的浓度范围为1.48～2.96 mg·L-1,细菌丰度为(3.32～16.6)×106个·ml-1,病毒丰度为(1.87～12.5)×107个·ml-1,病毒丰度与细菌丰度的比值(VBR)变化范围为4.09～12.77,平均值均为百花湖(BH)>阿哈湖入湖区(AHB)>阿哈湖湖心区(AHA).细菌和病毒丰度由湖水表层至底层呈减少趋势.两湖细菌丰度均与温度、pH、DO呈显著正相关,与电导率呈显著负相关,且与病毒丰度呈极显著性正相关.阿哈湖细菌丰度与DOC显著正相关.在阿哈湖湖心区,病毒丰度与DOC呈显著正相关.在阿哈湖入湖区,病毒丰度与DOC无相关性.百花湖中,细菌、病毒丰度均与DOC无相关性.     

Photodynamic Antifungal Therapy Against Chromoblastomycosis

Photodynamic therapy (PDT) is a minimally invasive approach, in which a photosensitizer compound is activated by exposure to light. The activation of the sensitizer drug results in several chemical reactions, such as the production of reactive oxygen species and other reactive molecules, which presence in the biological site leads to the damage of target cells. Although PDT has been primarily developed to combat cancerous lesions, this therapy can be employed for the treatment of several conditions, including infectious diseases. A wide range of microorganisms, including Gram-positive and Gram-negative bacteria, viruses, protozoa, and fungi, have demonstrated susceptibility to antimicrobial PDT. This treatment might consist in an alternative for the management of fungal infections. Antifungal photodynamic therapy has been successfully employed against Candida species, dermatophytes, and Aspergillus niger. Chromoblastomycosis is an infection that involves skin and subcutaneous tissues caused by the traumatic inoculation of dematiaceous fungi species, being that the most prevalent are Fonsecaea pedrosoi and Claphialophora carrionii. In the present work, the clinical applications of PDT for the treatment of chromoblastomycosis are evaluated. We have employed methylene blue as photosensitizer and a LED (Light Emitting Diode) device as light source. The results of this treatment are positive, denoting the efficacy of PDT against chromoblastomycosis. Considering that great part of the published works are focused on in vitro trials, these clinical tests can be considered a relevant source of information about antifungal PDT, since its results have demonstrated to be promising. The perspectives of this kind of treatment are analyzed in agreement with the recent literature involving antifungal PDT.     

Elimination of viruses from domestic wastewater: requirements and technologies

Domestic wastewater contains various pathogens, which, if not sufficiently eliminated, may enter the receiving water bodies and cause water-transmitted diseases. Among the waterborne pathogens, viruses may occur, survive and/or decay much differently from bacteria in water. In many cases, the diseases caused by viruses are more severe. Therefore, research efforts are mainly directed at the behavior of viruses in water environments, as well as the elimination of viruses from wastewater. In this paper, an overview of the occurrence of viruses in wastewater is presented, together with their categories, methods of detection and potential to cause waterborne diseases. As wastewater treatment plants are critical nodes for the influx and termination of virus transmission, the behavior of viruses at each stage of treatment is reviewed. Particular attention is paid to the unit operations, which play crucial roles in virus removals, such as coagulation and membrane filtration, and that for virus inactivation, such as chemical disinfection and UV irradiation. Future needs for the development of new technologies for virus elimination, source control, and finding more suitable indicators of viral pathogens are also highlighted.     

Recombinant viruses as tools to induce protective cellular immunity against infectious diseases.

Infections by intracellular pathogens such as viruses, some bacteria and many parasites, are cleared in most cases after activation of specific T cellular immune responses that recognize foreign antigens and eliminate infected cells. Vaccines against those infectious organisms have been traditionally developed by administration of whole live attenuated or inactivated microorganisms. Nowadays, research is focused on the development of subunit vaccines, containing the most immunogenic antigens from the particular pathogen. However, when purified subunit vaccines are administered using traditional immunization protocols, the levels of cellular immunity induced are mostly low and not capable of eliciting complete protection against diseases caused by intracellular microbes. In this review, we present a promising alternative to those traditional protocols, which is the use of recombinant viruses encoding subunit vaccines as immunization tools. Recombinant viruses have several interesting features that make them extremely efficient at inducing immune responses mediated by T-lymphocytes. This cellular immunity has recently been demonstrated to be of key importance for protection against malaria and AIDS, both of which are major targets of the World Health Organization for vaccine development. Thus, this review will focus in particular on the development of new vaccination protocols against these diseases.     

Virucidal activity of a scorpion venom peptide variant mucroporin-M1 against measles, SARS-CoV and influenza H5N1 viruses

Outbreaks of SARS-CoV, influenza A (H5N1, H1N1) and measles viruses in recent years have raised serious concerns about the measures available to control emerging and re-emerging infectious viral diseases. Effective antiviral agents are lacking that specifically target RNA viruses such as measles, SARS-CoV and influenza H5N1 viruses, and available vaccinations have demonstrated variable efficacy. Therefore, the development of novel antiviral agents is needed to close the vaccination gap and silence outbreaks. We previously indentified mucroporin, a cationic host defense peptide from scorpion venom, which can effectively inhibit standard bacteria. The optimized mucroporin-M1 can inhibit gram-positive bacteria at low concentrations and antibiotic-resistant pathogens. In this investigation, we further tested mucroporin and the optimized mucroporin-M1 for their antiviral activity. Surprisingly, we found that the antiviral activities of mucroporin-M1 against measles, SARS-CoV and influenza H5N1 viruses were notably increased with an EC₅₀ of 7.15 μg/ml (3.52 μM) and a CC₅₀ of 70.46 μg/ml (34.70 μM) against measles virus, an EC₅₀ of 14.46 μg/ml (7.12 μM) against SARS-CoV and an EC₅₀ of 2.10 μg/ml (1.03 μM) against H5N1, while the original peptide mucroporin showed no antiviral activity against any of these three viruses. The inhibition model could be via a direct interaction with the virus envelope, thereby decreasing the infectivity of virus. This report provides evidence that host defense peptides from scorpion venom can be modified for antiviral activity by rational design and represents a practical approach for developing broad-spectrum antiviral agents, especially against RNA viruses.     

Interactions of Bacillus spp. and plants--with special reference to induced systemic resistance (ISR)

Biological control of soil-borne pathogens comprises the decrease of inoculum or of the disease producing activity of a pathogen through one or more mechanisms. Interest in biological control of soil-borne plant pathogens has increased considerably in the last few decades, because it may provide control of diseases that cannot or only partly be managed by other control strategies. Recent advances in microbial and molecular techniques have significantly contributed to new insights in underlying mechanisms by which introduced bacteria function. Colonization of plant roots is an essential step for both soil-borne pathogenic and beneficial rhizobacteria. Colonization patterns showed that rhizobacteria act as biocontrol agents or as growth-promoting bacteria form microcolonies or biofilms at preferred sites of root exudation. Such microcolonies are sites for bacteria to communicate with each other (quorum sensing) and to act in a coordinated manner. Elicitation of induced systemic resistance (ISR) by plant-associated bacteria was initially demonstrated using Pseudomonas spp. and other Gram-negative bacteria. Several strains of the species Bacillus amyloliquefaciens, B. subtilis, B. pasteurii, B. cereus, B. pumilus, B. mycoides, and B. sphaericus elicit significant reductions in the incidence or severity of various diseases on a diversity of hosts. Elicitation of ISR by these strains has been demonstrated in greenhouse or field trials on tomato, bell pepper, muskmelon, watermelon, sugar beet, tobacco, Arabidopsis sp., cucumber, loblolly pine, and two tropical crops (long cayenne pepper and green kuang futsoi). Protection resulting from ISR elicited by Bacillus spp. has been reported against leaf-spotting fungal and bacterial pathogens, systemic viruses, a crown-rotting fungal pathogen, root-knot nematodes, and a stem-blight fungal pathogen as well as damping-off, blue mold, and late blight diseases. This progress will lead to a more efficient use of these strains which is worthwhile approach to explore in context of biocontrol strategies.     

Plant‐based oral vaccines against zoonotic and non‐zoonotic diseases

The shared diseases between animals and humans are known as zoonotic diseases and spread infectious diseases among humans. Zoonotic diseases are not only a major burden to livestock industry but also threaten humans accounting for >60% cases of human illness. About 75% of emerging infectious diseases in humans have been reported to originate from zoonotic pathogens. Because antibiotics are frequently used to protect livestock from bacterial diseases, the development of antibiotic‐resistant strains of epidemic and zoonotic pathogens is now a major concern. Live attenuated and killed vaccines are the only option to control these infectious diseases and this approach has been used since 1890. However, major problems with this approach include high cost and injectable vaccines is impractical for >20 billion poultry animals or fish in aquaculture. Plants offer an attractive and affordable platform for vaccines against animal diseases because of their low cost, and they are free of attenuated pathogens and cold chain requirement. Therefore, several plant‐based vaccines against human and animals diseases have been developed recently that undergo clinical and regulatory approval. Plant‐based vaccines serve as ideal booster vaccines that could eliminate multiple boosters of attenuated bacteria or viruses, but requirement of injectable priming with adjuvant is a current limitation. So, new approaches like oral vaccines are needed to overcome this challenge. In this review, we discuss the progress made in plant‐based vaccines against zoonotic or other animal diseases and future challenges in advancing this field.     

Effect of infectious factors on human and animal cytogenetic structures]

The analysis of blood leucocyte chromosomes has been carried out on 60 patients with different infectious diseases (influenza, measles, scarlet fever, and disentery), and on 47 patients immunized against measles, tick-born encephalitis, typhoid fever and brucellosis. The mutagenic influence of viruses on the genital cells of mice and on the human somatic cells in vitro was studied. Both viruses and bacteria appeared to be able to bring about different breaks in human and animal cells.     

Veterinary vaccines

Vaccination of animals for the prevention of infectious diseases has been practised for a number of years with little change in product composition. Recent advances in molecular biology, pathogenesis and immunology have laid the groundwork for the development of a new generation of veterinary vaccines based on pure subunits as well as live vectored bacteria and viruses. Along with novel methods of antigen preparation, the use of new adjuvants and delivery systems will permit targeting of the appropriate immune response as well as offering flexibility in terms of vaccination protocols. These new technologies are also being applied to the development of vaccines to enhance animal productivity and to control reproduction.     

Eukaryotic translation initiation factor 4E-mediated recessive resistance to plant viruses and its utility in crop improvement

The use of genetic resistance is considered to be the most effective and sustainable approach to the control of plant pathogens. Although most of the known natural resistance genes are monogenic dominant R genes that are predominant against fungi and bacteria, more and more recessive resistance genes against viruses have been cloned in the last decade. Interestingly, of the 14 natural recessive resistance genes against plant viruses that have been cloned from diverse plant species thus far, 12 encode the eukaryotic translation initiation factor 4E (eIF4E) or its isoform eIF(iso)4E. This review is intended to summarize the current state of knowledge about eIF4E and the possible mechanisms underlying its essential role in virus infection, and to discuss recent progress and the potential of eIF4E as a target gene in the development of genetic resistance to viruses for crop improvement.