Hepatitis B virus replication and tuberculin reactivity: studies in Alaska

In a previous study in 1982-1984 of southeast Asian refugees in Philadelphia, the authors found that hepatitis B virus carriers who reacted to a tuberculin (purified protein derivative (PPD)) skin test were more likely to be negative for the hepatitis B e antigen (HBeAg) than carriers who did not react to PPD. Because it was not known whether the PPD reactivity was due to natural infection or vaccination with bacille Calmette-Guérin (BCG), the authors conducted a further study in 1985 in Alaskan Native hepatitis B carriers, a group not vaccinated with BCG. The inverse association of HBeAg and PPD reactivity was confirmed across all age groups and was similar in magnitude to that observed in the refugee population. The host response to tubercle bacilli may inhibit the replication of hepatitis B virus. If the host response to BCG is similar, BCG vaccination may be of therapeutic value in chronic hepatitis B infection.     

Manual compression device for fluoroscopy

A device for manual compression and palpation during supine fluoroscopy has been designed. It enables effective use of the physiologic grasping and lever force potentials of the hand and wrist. The device permits optimal fluoroscopic palpation and compression techniques and prevents direct exposure to the lead-gloved hand.     

Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study

Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study. Cephalalgia 1994;1'4:270-1. Oslo. ISSN 0333-1024We prospectively studied over two years the incidence of headache as the initial and isolated clinical manifestation of adult patients suffering from intracranial tumors ( n = 183). Fifteen patients (8%) exhibited headache as their first and isolated clinical manifestation. Age, sex, neoplasm localization, or pathological diagnosis did not correlate with the presence of headache. Posterior fossa location and hydrocephalus, though not reaching statistical significance, were more frequent in patients who presented with headache as the first symptom. At the moment of diagnosis, 59 (31%) of the patients admitted to headache, though only I out of the 15 patients starting as headache still had this symptom as the only manifestation. From our experience in adults, isolated headache for longer than 10 weeks will only exceptionally be secondary to an intracranial neoplasm.     

Identification and analysis of bacterial protein secretion inhibitors utilizing a SecA-LacZ reporter fusion system

Protein secretion is an essential process for bacterial growth, yet there are few if any antimicrobial agents which inhibit secretion. An in vivo, high-throughput screen to detect secretion inhibitors was developed based on the translational autoregulation of one of the central protein components, SecA. The assay makes use of a SecA-LacZ fusion reporter construct in Escherichia coli which is induced when secretion is perturbed. Several compounds, including two natural product extracts, which had the ability to induce the reporter fusion were identified and the MICs of these compounds for Staphylococcus aureus strain MN8 were found to be < or =128 microg/ml. Enzyme-linked immunosorbent assay, Western blotting, and immunoprecipitation techniques were used to analyze the affects of these compounds on protein secretion. Six representative compounds presented here appear to be bona fide secretion inhibitors but were found to have deleterious effects on membranes. It was concluded that, while the method described here for identifying inhibitors of secretion is valid, screens such as this, which are directed against the membrane-bound portion of a pathway, may preferentially identify compounds which affect membrane integrity.     

个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系

目的：分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。 方法：选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料（骨水泥、硅橡胶）组40例,根据颅骨缺损面积又分为大面积（≥36cm2）组17例和小面积（〈36cm2）组23例;覆盖性材料（钛网）组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描（层厚1.5mm）,三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症：头痛、积液、松动。 结果：75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%（63/75）患者感到基本或完全恢复了原有容貌。手术并发症：嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。 结论：个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。     

Direct quantitation of IgG subclasses 1, 2, and 3 bound to red cells by Rh1 (D) antibodies

The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies.     

Endogenous DNA damage and testicular germ cell tumors

Testicular germ cell tumors are comprised of two histologic groups, seminomas and non-seminomas. We postulated that the possible divergent pathogeneses of these histologies may be partially explained by variable levels of net endogenous DNA damage. To test our hypothesis, we conducted a case–case analysis of 51 seminoma and 61 non-seminoma patients using data and specimens from the Familial Testicular Cancer study and the U.S. Radiologic Technologists cohort. A lymphoblastoid cell line was cultured for each patient and the alkaline comet assay was used to determine four parameters: tail DNA, tail length, comet distributed moment (CDM) and Olive tail moment (OTM). Odds ratios (OR) and 95% confidence intervals (95% CI) were estimated using logistic regression. Values for tail length, tail DNA, CDM and OTM were modelled as categorical variables using the 50th and 75th percentiles of the seminoma group. Tail DNA was significantly associated with non-seminoma compared with seminoma (OR_{50th percentile} = 3.31, 95% CI: 1.00, 10.98; OR_{75th percentile} = 3.71, 95% CI: 1.04, 13.20; p for trend = 0.039). OTM exhibited similar, albeit statistically non-significant, risk estimates (OR_{50th percentile} = 2.27, 95% CI: 0.75, 6.87; OR_{75th percentile} = 2.40, 95% CI: 0.75, 7.71; p for trend = 0.12) whereas tail length and CDM showed no association. In conclusion, the results for tail DNA and OTM indicate that net endogenous levels are higher in patients who develop non-seminoma compared with seminoma. This may partly explain the more aggressive biology and younger age-of-onset of this histologic subgroup compared with the relatively less aggressive, later-onset seminoma.     

Metal hypersensitivity: can it mimic infection?

Metal hypersensitivity leading onto hardware rejection is reported as a rare phenomenon. If not suspected, it can be a harrowing experience for the patient because it can lead to a seemingly never-ending cycle of tests and procedures. This case highlights the fact that although metal hypersensitivity is rare, it should be included in the differential once infection has been excluded.