Nocardiosis of the lung: chest radiographic findings in 21 cases

Pulmonary manifestations of nocardial infection were present in 21 patients, with microbiologic proof in all and pathologic proof in 12. An analysis of the findings in these patients, combined with a review of previous reports of nocardiosis, suggests several important conclusions for radiologists. First, nocardiosis may occur in otherwise healthy persons but is most common in compromised patients, especially those being treated with anti-inflammatory agents, particularly corticosteroids, for chronic obstructive pulmonary disease and other systemic diseases. As pathologic manifestations are both suppurative and granulomatous, the chest radiographic manifestations are pleomorphic and not specific. Consolidations and large irregular nodules, often cavitary, are most common; nodules, masses, and interstitial patterns also occur. Pleural effusions are quite common, and lymph nodes may be enlarged. Difficulty and slowness of culture growth, along with the lack of a serologic test for nocardiosis, necessitate its inclusion in the differential diagnosis for both compromised and noncompromised patients in whom an apparent pulmonary infection cannot be rapidly diagnosed.     

Role of penicillin-binding protein 4 in expression of vancomycin resistance among clinical isolates of oxacillin-resistant Staphylococcus aureus

It has been reported that penicillin-binding protein 4 (PBP4) activity decreases when a vancomycin-susceptible Staphylococcus aureus isolate is passaged in vitro to vancomycin resistance. We analyzed the PBP profiles of four vancomycin intermediately susceptible S. aureus (VISA) clinical isolates and found that PBP4 was undetectable in three isolates (HIP 5827, HIP 5836, and HIP 6297) and markedly reduced in a fourth (Mu50). PBP4 was readily visible in five vancomycin-susceptible, oxacillin-resistant S. aureus (ORSA) isolates. The nucleotide sequences of the pbp4 structural gene and flanking sequences did not different between the VISA and vancomycin-susceptible isolates. Overproduction of PBP4 on a high-copy-number plasmid in the VISA isolates produced a two- to threefold decrease in vancomycin MICs. Inactivation of pbp4 by allelic replacement mutagenesis in three vancomycin-susceptible ORSA strains (COL, RN450M, and N315) led to a decrease in vancomycin susceptibility, an increase in highly vancomycin-resistant subpopulations, and decreased cell wall cross-linking by high-performance liquid chromatography analysis. Complementation of the COL mutant with plasmid-encoded pbp4 restored the vancomycin MIC and increased cell wall cross-linking. These data suggest that alterations in PBP4 expression are at least partially responsible for the VISA phenotype.     

长期运动对十二指肠黏膜一氧化氮合成和铁贮存的调控效应

目的:观察长期运动对十二指肠黏膜一氧化氮合成和铁贮存的影响及一氧化氮对铁贮存的调节作用。方法:实验于2004-04/09在江苏大学医学院铁代谢研究室完成。①健康雌性SD大鼠40只,随机分为静息组、静息并应用一氧化氮抑制剂组、运动组、运动并应用一氧化氮抑制剂组,每组10只。②静息并应用一氧化氮抑制剂组和运动并应用一氧化氮抑制剂组饮用水中含有一氧化氮抑制剂(1g/L),运动组和运动并应用一氧化氮抑制剂组的大鼠游泳3个月。③3个月后分析各组大鼠血浆铁饱和度,一氧化氮浓度以及十二指肠黏膜一氧化氮含量和非血红素铁含量。结果:实验过程中死亡11只,进入结果分析29只(静息组8只、静息并应用一氧化氮抑制剂组5只、运动组8只、运动并应用一氧化氮抑制剂组8只)。①运动及一氧化氮抑制剂对大鼠血浆铁饱和度和一氧化氮浓度的影响:运动组的血浆铁饱和度低于静息组(P<0.01);运动并应用一氧化氮抑制剂组的血浆铁饱和度低于静息并应用一氧化氮抑制剂组(P<0.05),并且高于运动组(P<0.05)。运动组血浆一氧化氮浓度显著高于静息组(P<0.01);运动并应用一氧化氮抑制剂组的血浆一氧化氮浓度低于运动组(P<0.01),与静息并应用一氧化氮抑制剂组差别不显著(P>0.05)。②运动及一氧化氮抑制剂对大鼠十二指肠黏膜一氧化氮和非血红素铁含量的影响:运动组的十二指肠一氧化氮含量高于静息组(P<0.01);静息并应用一氧化氮抑制剂组的一氧化氮含量低于静息组(P<0.01);运动并应用一氧化氮抑制剂组的一氧化氮含量低于运动组(P<0.01),但高于静息并应用一氧化氮抑制剂组(P<0.01),与静息组差别不显著。与静息组比较,运动组和静息并应用一氧化氮抑制剂组的十二指肠黏膜非血红素铁含量均降低(P<0.05)。结论:静息状态下十二指肠黏膜细胞一氧化氮合成具有较高的紧张性,可能参与维持非血红素铁含量。长期运动可刺激十二指肠黏膜一氧化氮合成,降低铁贮存。但其机制是否涉及运动诱导的一氧化氮的直接作用以及是否参与铁吸收的调节有待于进一步研究。     

DIGITAL ISCHAEMIA: AN UNUSUAL PRESENTATION OF DYSBARISM

SUMMARY Dysbaric symptoms following ascent from a scuba dive are due to symptomatic nitrogen or air emboli with clear patterns of associated injury. This case report highlights an unusual presentation of dysbaric injury treated successfully with a prostacyclin analogue.     

A randomized,double-blind trial of the effect of metronidazole on pain after closed hemorrhoidectomy

PURPOSE: Patients consider hemorrhoidectomy to be a painful operation. Attempts to reduce the length of inpatient stay have concentrated mainly on a reduction in postoperative pain. Metronidazole has been shown to reduce pain after open hemorrhoidectomy. The aim of this study was to evaluate the effect of metronidazole after closed hemorrhoidectomy. METHODS: Thirty-eight patients undergoing closed hemorrhoidectomy were randomly allocated to receive metronidazole 400 mg (n = 18) or placebo (n = 20) three times daily for seven postoperative days. All patients received a stool softener and analgesics perioperatively. Linear analog scales were used to assess expected pain, actual pain and patient satisfaction. Time to first bowel movement, return to normal activity, complications, and use of additional analgesics were recorded. RESULTS: Both groups of patients experienced less pain than expected. Patients in the metronidazole group required fewer additional analgesics postoperatively (6.3 vs. 26.3 percent), and satisfaction scores in the placebo group were higher at one week (0.5 vs. 2.5), although these differences were not statistically significant. There were no differences in pain actually experienced, time to first bowel movement, return to normal activity, or complications between the two groups. Satisfaction scores at six weeks for all patients were relatively high, with no significant difference between the groups. CONCLUSION: Closed hemorrhoidectomy results in high patient satisfaction and low pain scores. The use of postoperative metronidazole did not reduce postoperative pain.     

The Role of Resilience in the Clinical Management of Chronic Pain

Chronic pain affects more individuals than does cancer, heart disease, and diabetes combined. Yet, our treatment options remain remarkably limited. Often, highly effective psychotherapeutic approaches are limited by many barriers such as access, reimbursement, and acceptability; however, resilience-based positive activity interventions could offer a promising alternative. These interventions are engaging, non-stigmatizing, and do not require a mental health professional for their provision. This article reviews the new, but limited, research exploring the use of positive activity interventions for the treatment of patients with chronic pain. The related psychological and biological mechanisms are addressed, as are suggestions for more systematically evaluating the potential for positive activity interventions to become an adjunct to or stand-alone intervention strategy for patients with chronic pain.     

Non-specific (entropic) forces as major determinants of the structure of mammalian chromosomes

Four specific forces (H-bonds, van der Waals forces, hydrophobic and charge interactions) shape the structure of proteins, and many biologists assume they will determine the shape of all structures in the cell. However, as the mass and contour length of a human chromosome are ~7 orders of magnitude larger than those of a typical protein, additional forces can become significant. We review evidence that additional non-specific (entropic) forces are major determinants of chromosomal shape and position. They are sufficient to drive the segregation (de-mixing) of newly replicated DNA to the poles of bacterial cells, while an entropic centrifuge can both form human chromosomes into territories and position them appropriately in nuclei; more locally, a depletion attraction can loop bacterial and human genomes.     

Impact of Body Mass Index on Left Ventricular Function

Background

Obesity is associated with increased cardiovascular morbidity and mortality. A direct effect of isolated obesity on cardiac function is not well established. The study was designed to determine the direct effect of various grades of isolated obesity on echocardiographic indices of systolic and diastolic left ventricular function.

Methods

Fifty one obese and 25 normal weight, serving personnel without any other pathological condition were studied. Group I (n=25) consisted of subjects with normal weight and body mass index (BMI <25kg/m²), Group II (n=34) of overweight subjects (BMI 25-29.9 kg/m²) and Group III (n=17) of obese subjects (BMI >30 kg/m²). Echocardiographic indices of systolic and diastolic function were obtained and dysfunction was assumed when at least two values differed by ≥ 2 SD from the normal weight group.

Result

Ejection fraction, fractional shortening were increased (p<0.05) in Group II and III. Left ventricular dimensions were increased (p< 0.001) but relative wall thickness was unchanged. Systolic dysfunction was not observed in any of the obese patients. The mitral valve pressure half time (p< 0.01), left atrial diameter (p < 0.01) and the deceleration time were increased (p< 0.01) in obese subjects, while other diastolic variables were unchanged. No difference were found between obesity subgroups. Subclinical diastolic dysfunction was more prevalent among obese subjects. BMI correlated significantly with indices of left ventricular systolic and diastolic function.

Conclusion

Subclinical left ventricular diastolic dysfunction was noted in all grades of obesity which correlates with BMI.Key Words: Obesity, Systolic function, Diastolic function, Echocardiography     

Calculating the insulin to carbohydrate ratio using the hyperinsulinaemic-euglycaemic clamp-a novel use for a proven technique

BACKGROUND: In patients with type 1 diabetes, three main variables need to be assessed to optimize meal-related insulin boluses: pre-meal blood glucose (BG), insulin to carbohydrate ratio (I : C), and basal insulin. We are presenting data for a novel use of the hyperinsulinaemic-euglycaemic clamp (HEC) in patients with type 1 diabetes that minimizes the impact of these variables and can be used to determine the I : C. METHODS: Ten subjects (six men and four women) using continuous subcutaneous insulin infusion (CSII) pumps were recruited for this study [24-65 years; BMI 27.1 +/- 4.9 kg/m(2); A1C 7.2 +/- 1.4% (mean +/- SD)]. The HEC used a primed continuous intravenous insulin infusion of 40 mU/m(2)/min and a variable infusion of 20% glucose to maintain BG at 90 mg/dL. After subjects were in steady state (SS) for 50 min, a standardized meal (40% of total calories/day - 30% carbohydrate, 30% protein, 40% fat) was consumed. Subjects gave the insulin bolus with their CSII pump. No changes were made in the glucose infusion rate. RESULTS: Mean BG at SS was 85.7 +/- 10.4 mg/dL. Peak BG was 115.0 +/- 12.7 mg/dL at 68.5 +/- 8.8 min after the meal. Mean I : C was 1 : 9.3 +/- 1.7 (range 1 : 7-1 : 12). Insulin sensitivity varied from 1.9 to 9.1 mg/kg/min. CONCLUSIONS: The HEC can be used to reduce confounding factors and to determine the I : C. As a first estimate of the I : C in patients with type 1 diabetes, it is recommended to start with a ratio of 1 : 9.3 and to measure post-prandial BG at 70 min.