Mycetoma of the calf

 Actinomycetous infections typically involve either the head and neck or the extremities following a traumatic implantation. Classic clinical associations are draining sinus tracts. This case report describes the pathologic and MR findings of a relatively acute mycetomatous process involving the soft tissues. Pathologic findings in this case included an occasional granule composed of gram positive, thin branching elements. These and other findings were consistent with actinomycetes bacterium infection. The discussion centers around the use of MR, both with and without gadolinium, in evaluating this type of granulomatous infection. Infiltration of the adjacent subcutaneous tissues was easier to appreciate on both the T1-weighted images without gadolinium and the T1-weighted images with gadolinium when compared to the T2-weighted images. Signal characteristics as described in this case report may suggest a granulomatous process.     

Professor Ahmed Shafik (1933–2007)

Most cases of anal abscess are caused by anal fistula and invasion of the surrounding tissues by a mixed colonic flora. Treatment consists of excision of the abscess and, in case of fistula, fistulectomy. Primary anorectal and perianal forms of actinomycosis are very rare and caused by actinomyces, as ubiquitous anaerobics bacterium. We report a case of perianal actinomycosis. The patient had a short history of painless perineal induration without fever and leukocytosis with normal results at routine blood examination. After excision, sulfur granules drained from the cavity and pathological investigations indicated perianal actinomycosis. Appropriate surgery and antibiotic treatment healed the perianal infection. After exclusion of possible diagnoses such as Crohn’s disease, tuberculosis and malignant growths, the rare case of perianal actinomycosis should be considered in the differential diagnosis of painless perianal masses.     

Functional analysis of different regions of the positive-acting CYS3 regulatory protein of Neurospora crassa

In the filamentous fungus Neurospora crassa during conditions of sulfur limitation, CYS3, a major positive-acting regulatory protein, turns on the expression of an entire set of genes which encode permeases and enzymes involved in the acquisition of sulfur from environmental sources. CYS3 functions as a homodimeric protein and possesses a b-Zip domain that confers sequence-specific DNA binding. Expression of various hybrid GAL4-CYS3 fusion proteins in yeast was used to detect regions involved in gene activation. An amino-terminal serine/threonine-rich domain of CYS3 alone strongly activated expression of β-galactosidase, the yeast reporter. Moreover, mutant CYS3 proteins with amino-acid substitutions in this region that showed increased expression in Neurospora also displayed an enhanced activation potential in yeast. The cys-3 gene of the exotic N. crassa Mauriceville strain and of N. intermedia were cloned and demonstrated to be functional for gene activation and for sulfur-mediated regulation by complementation of a loss-of-function cys-3 mutation. The amino-terminal serine/threonine-rich region is highly conserved in these two CYS3 proteins, in agreement with the possibility that it serves as the activation domain. Surprisingly, an extended promoter region of the cys-3 gene in the Mauriceville strain and in N. intermedia was very well conserved with that of the standard N. crassa gene, including the presence of three CYS3-binding sites possibly involved in autogenous control. Results are presented which indicate that synthesis of the CYS3 regulatory protein is highly regulated and can be detected in the nucleus of cells subjected to sulfur de-repression, but is not found in the nucleus or the cytoplasm of S-repressed cells. The amino-acid substitutions of the CYS3 protein present in a temperature-sensitive cys-3 mutant and in a second-site revertant of a cys-3 null mutation are presented and are shown to affect their DNA-binding activities. Received: 9 January / 5 March 1998     

C—2位硫桥式四环氟喹诺酮抗菌素W1的合成与抗菌活性

合成了一个新的C－2位硫桥式四环氟喹诺酮抗菌素7－氟－8－[(1S,4S)-5－甲基－2,5－二氮杂双环[2.2.1]庚烷-2]-9,1-(环氧亚甲基）－5－氧－5H噻唑并[3,2-a]喹啉－4－羧酸盐酸盐（W1）,未文献报道。W1经元素分析、红外光谱、核磁共振光谱作了结构鉴定,并通过两倍琼脂稀释法对其MICs进行了测定,以氧氟沙星作对照,结果表明：W1显示极好的抗菌活性,其抗G^ 菌（包括耐甲氧西林的金黄色葡萄球菌）的活性比氧氟沙星至少强4倍,抗G^-菌（包括绿脓杆菌）的活性比氧氟沙星至少强两倍。     

In vitro and in vivo uptake of nickel sulfides by rat lymphocytes

The uptake, the biological transformation and the interaction with cellular constituents of Ni₃S₂ and NiS have been studied in vitro and in vivo on rat lymphocytes. NiS crystals are phagocytized in vitro and no structural degradation is observed within the first 3 days of exposure. Energy dispersive spectrometry (EDS) reveals a slight dissolution characterized by the loss of sulfur. Ni₃S₂ is degraded in the extracellular space to minute particles (50–100 nm) covering the cell membrane. Smaller intracellular particles (10–30 nm) are found selectively bound to mitochondria, endoplasmic reticulum, Golgi vesicles, nuclear membranes, and the euchromatinic part of nuclei. EDS analyses reveal that the particles bound to cell membranes and euchromatin no longer contain sulfur but phosphorus and nickel as inorganic compounds. This observation suggests the formation of a Ni/P complex with the phosphate groups either of membranous phospholipids or of nuclear RNA or DNA. A similar uptake and transformation process of Ni₃S₂ is observed on lymphocytes after in vivo incubation. This leads us to consider lymphocytes as target cells, as compared with other cell types where the Ni₃S₂ uptake occurs only partially. The present findings show a difference of uptake and biological transformation between Ni₃S₂ and NiS. The identical results obtained after in vitro and in vivo bioassays enhance the in vitro experiments, at least for this cell type.     

二氧化硫气体对小鼠肺组织细胞周期的影响

目的:检测小鼠吸入二氧化硫(SO2)慢性中毒后肺组织细胞周期的变化.方法:以昆明种小鼠作为实验对象,设计SO2 3个剂量组和1个阴性对照组,通过动式吸入染毒,于染毒6个月后,采用流式细胞仪检测肺组织的细胞周期.结果:各剂量组细胞周期中G0/G1(%)随染毒剂量的增加而减少,且各组间G0/G1(%)有显著性差异(P＜0.05),其中高剂量组与阴性对照组比较,有显著性差异(P＜0.01);各剂量组S(%)随染毒剂量的增加而增高,各剂量组S%有显著性差异(P＜0.01),其中高、中剂量组与阴性对照组比较,均有显著性差异(P＜0.01);G2/M(%)随染毒剂量的增加而增高,且各组间G2/M(%)有显著性差异,其中高剂量组与阴性对照组比较,有显著性差异(P＜0.01).结论:小鼠吸入SO2慢性中毒后,在细胞周期中,G0/G1期细胞所占百分数随染毒剂量的增加而减少,而S期与G2/M期细胞所占百分数增高,提示小鼠肺组织细胞处于较高的增殖状态.     

^99^Tc^m-硫胶体不同制备条件及注射部位对乳腺癌前哨淋巴结检出的影响

目的 观察99^Tc^m-SC不同配置条件及注射部位对乳腺癌前哨淋巴结（SLN）检出的影响,探讨进行乳腺癌SLN活检术（SLNB）的最佳方法.方法 制备99^Tc^m-SC时将煮沸时间分别控制在3 min（显像剂1）和5 min（显像剂2）,分别测定显像剂1和显像剂2放置10 min、1h、2h和4h的放化纯及胶体大小分布.将147例乳腺癌患者用抽签法分成3组：A组40例,于乳晕周围乳腺组织内注射显像剂1;B组40例,于乳晕周围乳腺组织内注射显像剂2;C组67例,于肿块周围乳腺组织内注射显像剂2.所有患者均于术前0.5～1 h行SPECT/CT显像,并在肿块上方皮下注射蓝染料.比较3组患者腋窝及内乳SLN显像成功率及术中检出率.分别采用两独立样本t检验、单因素方差分析和r检验对相关数据进行统计学分析.结果 显像剂1和显像剂2的放化纯在放置10 min、1h、2h及4h时差异均无统计学意义（t=-0.267、-0.794、0.826和-0.977,均P＞0.05）;显像剂2与显像剂1相比,粒径＜100nm的粒子所占百分比明显减少[（65.25±3.56）％与（73.72±2.36）％;t=6.436,P＜0.05],平均有效粒径明显增大[（75.59±7.04） nm与（45.27±6.42） nm;t=7.315,P＜0.05）.3组患者内乳SLN的检出率分别为70.0％ （28/40）、47.5％ （19/40）和17.9％ （12/67）,差异有统计学意义（x2=29.525,P＜0.05）;3组患者腋窝SLN的检出率分别为100％ （40/40）、95.0％（38/40）及97.0％（65/67）,差异无统计学意义（r=2.686,P＞0.05）.结论 通过缩短煮沸时间减小99^Tc^m-SC胶体粒径,经肿瘤上方皮下注射蓝染料、乳晕周围乳腺组织内注射核素及SPECT/CT断层显像,可获得较好的乳腺癌腋窝和内乳SLN检出效果.     

Cadmium accumulation,sub-cellular distribution and chemical forms in rice seedling in the presence of sulfur

Changes in cadmium (Cd) accumulation, distribution, and chemical form in rice seedling in the joint presence of different concentrations of sulfur (S) remain almost unknown. Therefore, the indoor experiments were performed to determine the accumulation, sub-cellular distribution and chemical forms of Cd under three S levels in rice seedling for the first time. The result showed that Cd accumulation in rice roots was more than in shoots. Sub-cellular distribution of Cd in rice roots and shoots indicated that the largest proportion of Cd accumulated in cell walls and soluble fractions. As S supply increased, the proportion of Cd in cell walls reduced, while it increased in the soluble fractions. The majority of Cd existed in inorganic form, and then gradually changed to organic forms that included pectates and proteins with increased S supply. The results showed that S supply significantly influenced Cd accumulation, distribution, and chemical forms, suggesting that S might provide the material for the synthesis of sulfhydryl protein and thereby affect Cd stress on plants. These observations provided a basic understanding of potential ecotoxicological effects of joint Cd and S exposure in the environment.     

芥子气致肝脾损伤的研究现状

芥子气(SM)是一种战争中常用的化学毒剂,其致死、致伤率高,且伴随长期慢性伤害。其液气态可能损伤人体不同部位(如,呼吸道、皮肤、眼部等),近年来,SM损伤肝脾也备受人们关注。本文结合SM的毒理特征,对其造成肝、脾损伤的有关问题作一综述。     

学龄前儿童口腔中挥发性硫化物的检出情况及其相关因素

目的:了解学龄前儿童口腔中挥发性硫化物的检出情况,分析引起学龄前儿童口臭的主要相关因素,为儿童口臭和相关疾病的预防和治疗提供依据. 方法:对北京市某幼儿园170名4~6岁学龄前儿童口腔中挥发性硫化物( volatile sulfur compounds,VSC)含量和口腔健康状况进行检查,对儿童家长进行问卷调查,挥发性硫化物的检测使用便携式气相色谱仪OralChromaTM. 使用SPSS 13. 0软件包,进行VSC与口腔健康状况和行为等的单因素和多因素分析. 结果:单因素分析结果显示,检出口臭的儿童占全部受检人数的34. 4%. 女童口腔中硫化氢( hydro-gen sulfide,H2S)[(1.59 ±2.41) ng/10 mL]和VSC总量[(2.14 ±4.42) ng/10 mL]高于男童(P<0.05). 舌苔指数高的儿童的H2S[舌苔面积(1.68 ±2.48) ng/10 mL,舌苔厚度(2.18 ±2.69) ng/10 mL)和VSC总量[舌苔面积(2. 26 ± 4. 31) ng/10 mL,舌苔厚度(2. 41 ± 3. 02) ng/10 mL]高于舌苔指数低的儿童(P<0. 01). 简化软垢指数记分值≥2的位点数值与甲硫醇(methyl mercaptan,CH3SH)和二甲基硫[dimethyl sulfide,(CH3)2S]浓度呈正相关(P<0.01);母亲受教育程度在本科及以上的儿童口腔中H2S值[(1.19 ±1.62)ng/10 mL]显著低于母亲教育程度在本科以下的儿童(P<0. 01);甜食进食频率高的儿童H2S浓度[(1. 04 ± 1. 55) ng/10 mL]低于频率低的儿童(P<0. 01);有张口呼吸习惯的儿童CH3SH和(CH3)2S浓度[(0. 29 ± 1. 92) ng/10 mL,(0. 37 ± 2. 06) ng/10 mL]显著高于没有张口呼吸习惯的儿童(P<0. 05). Logistic多因素分析结果显示,舌苔指数高、母亲教育程度低的儿童VSC高于舌苔指数低和母亲教育程度高的儿童. 结论:学龄前儿童口臭检出率高,性别、舌苔指数、软垢指数、母亲教育程度、甜食进食频率、张口呼吸等因素是儿童口臭的相关影响因素,不同影响因素导致不同VSC成分的改变.