The posterior epidural ligaments: a cadaveric and histological investigation in the lumbar region

Purpose. Incidental durotomy is a relatively common complication for patients undergoing posterior spinal surgery. Delineating anatomical variants in the posterior lumbar spinal canal is crucial in reducing future rates of incidental durotomy. Materials and Methods. The ligamentous attachments between the dura mater and ligamentum flavum in the lumbar region of 17 soft-fixed cadavers were investigated. The lumbar vertebral columns were removed, and cross-sectional dissection was performed at levels L1-S1. Anterior retraction of the dorsal dura mater identified attachments between the dorsal surface of the dura mater and the ligamentum flavum. Histological staining of the ligamentous attachments was carried out with hematoxylin and eosin (H&E) and elastic van Gieson (EVG). Results. Posterior epidural ligaments were present in 9 (52.9%) cadavers. Nine (9) separate ligaments were identified in these cadavers, with 3 (33.3%) at L3/L4, 5 (55.5%) at L4/L5, and 1 (11.1%) at L5/S1. Histology confirmed the presence of poorly differentiated collagen-based connective tissue, distinct from the normal anatomy. Conclusions. This study confirms the presence of multiple dorsomedial posterior epidural ligaments at the main sites for posterior spinal surgery (L3-S1). An intraoperative awareness of the variability of such connections may be an important step in reducing static rates of incidental durotomy.

Microwave response of superconducting YBa2Cu3O(7-δ) nanowire bridges sustaining the critical depairing current: evidence of Josephson-like behavior

We have investigated the zero-field critical supercurrent of YBa(2)Cu(3)O(7-δ) bridges patterned from 50 nm thick films as a function of bridge width, ranging from 2 μm to 50 nm. The critical current density monotonically increases for decreasing bridge width even for widths smaller than the Pearl length. This behavior is accounted for by considering current crowding effects at the junction between the bridge and the wider electrodes. Comparison to numerical calculations of the current distributions in our bridge geometries of various widths yields a (local) critical current density at 4.2 K of 1.3×10(8) A/cm(2), the Ginzburg Landau depairing current density. The observation of up to 160 Shapiro-like steps in the current voltage characteristics under microwave irradiation substantiates the pristine character of our nanobridges with cross sections as small as 50×50 nm(2).

Composition and Antimicrobial Activity of the Essential Oil from Leaves of Curcuma longa L. Kasur Variety

The essential oil from the leaves of Curcuma longa L. Kasur variety grown in Pakistan was extracted by hydro-distillation. Chemical constituents of the essential oil were identified by gas chromatography/mass spectrometry. The chromatographic analysis of oil showed 25 constituents, out of which nine chemical constituents were identified. The eucalyptol (10.27%) was the major component of the essential oil. α-pinene (1.50%), β-phellandrene (2.49%), β-pinene (3.57%), limonene (2.73%), 1,3,8-p-menthatriene (1.76%), ascaridole epoxide (1.452%), 2-methylisoborneol (2.92%), 5-isopropyl-6-methyl-hepta-3, dien-2-ol (2.07%) were also present in considerable quantity. The antimicrobial properties of leaves of Curcuma longa were tested by disc diffusion method against various human pathogens, including eight fungal and five bacterial strains. Essential oil showed maximum resistance against Fusarium miniformes MAY 3629 followed by Bacillus subtilis ATCC 6633 whereas; it exhibited least resistance against Fusarium oxysporium ATCC 48122. The results of the antimicrobial assay revealed that essential oil showed significant inhibitory activity against the tested organisms.

Percutaneous tracheotomy: Forceps vs. cone dilatation techniques

Background:

Percutanoeous tracheotomy (PT) is a minimal invasive procedure alternative to surgical tracheotomy. PT offers an added advantage of enormous decrease of time interval between decision of doing tracheotomy and actually doing it. Moreover hazards of patient transport can be avoided as it can be safely performed at the bedside. We started doing PT in 2003 and performed 100 cases using forceps dilatation. Later we switched over to cone dilatation where we performed 215 cases. This study aims to compare two techniques of forceps vs. cone dilatation methods for PT.

Methods:

A total of 100 cases of PT were performed starting from December 2003 to August 2005 using the forceps dilatation method (group A). Further 215 cases were conducted (group B) from September 2003 to July 2008 using the cone dilatation method. Time of performing both procedures was recorded. Also incidence of complications was also recorded in both groups.

Results:

The incidence of minor bleeding in group A was 9%, whereas in group B was 5.58%. Major bleeding occurred in two patients in group B. Both cases suffered of pneumothorax and emphysema. One patient developed life-threatening tension pneumothorax and required cardio pulmonary resuscitation. This was one case in this series, in which the procedure has contributed to patient's morbidity. Guide wire-related technical difficulties were seen in 2% of the cases in group A, and 3.7% of cases in group B.

Conclusion:

forceps dilatation PT is superior to the cone dilatation technique in terms of safety. Further studies are needed to confirm our results.

Phylogenetic relationships among Saccharum clones in Pakistan revealed by RAPD markers

Forty sugarcane genotypes (clones), including elite lines, commercial cultivars of Saccharum officinarum and S. barberi clones, were fingerprinted with 30 RAPD markers, using a PCR-based marker assay. The genetic distance for RAPD data was determined according to Nei, and relationships between accessions were graphed in a dendrogram. Genetic distance values ranging from 16.2 to 86.3% were observed among the 40 sugarcane accessions. The lowest genetic distance was found between genotypes US-406 and US-186. These two genotypes differed from each other in only 25 bands with 15 different primers. Genotypes Col-54 and CP-72-2086 were the second most similar group, with a genetic distance of 19.46%. The most dissimilar of all the accessions were CP-77-400 and US-133, with a genetic distance of 86.3%. RAPD fingerprints help sugarcane breeders clarify the genetic pedigree of commercial sugarcane varieties and can be used to evaluate the efficiency of conventional breeding methods.

Genetic studies of "noble cane" for identification and exploitation of genetic markers

Forty genotypes (clones) of sugarcane, including elite lines, commercial cultivars of Saccharum officinarum and clones of S. barberi were fingerprinted with 50 SSR markers using a PCR-based marker assay. Nei's genetic distances for SSR data were determined and relationships between accessions were portrayed graphically in the form of a dendrogram. Genetic distance values ranging from 0.60 to 1.11 were observed among the 40 sugarcane accessions. The shortest genetic distance of 0.60 was seen between genotypes US-804 and US-130. These two genotypes differed from each other only in 10 bands, with 20 primers. The most dissimilar of the accessions were CP-77-400 and US-133, with a genetic distance of 1.11. SSR fingerprints can help sugarcane breeders to clarify the genetic pedigree of commercial sugarcane varieties and evaluate the efficiency of breeding methods.

DNA profiling of sugarcane genotypes using randomly amplified polymorphic DNA

DNA profiles of 40 sugarcane genotypes were constructed with 30 RAPD markers. Sugarcane genotypes of both Saccharum officinarum and S. barberi were included in this study. Multiple alleles were detected from each RAPD; there was a high level of polymorphism. On average, 7.93 alleles were produced per primer, giving a total of 238 alleles. The genetic distances between these genotypes were assessed with the POPGENE DNA sequence analysis software. A dendrogram was constructed from these data; cultivated species of sugarcane formed clusters with S. barberi genotypes. The 40 genotypes were clustered into two main groups; genetic distances ranged from 20.29 to 64.66%. These RAPD fingerprints will help sugarcane breeders to evaluate the efficiency of current conventional breeding methods and will help characterize the genetic pedigree of commercial sugarcane varieties. These data will also be valuable for conservation and utilization of the genetic resources in germplasm collections.

Prevention of beta-thalassemia in a large Pakistani family through cascade testing

BACKGROUND

We report cascade testing of a large Pakistani family for beta-thalassemia alleles. The family was still practicing consanguineous marriages and was at risk of having more affected births.

OBJECTIVE

The objective of this study was to show that identification of disease carriers in families with index cases in order to create awareness about disease and provide genetic counseling would result in reduction of the frequency of beta-thalassemia in Pakistan.

METHODS

In this large family with an index case, 27 available living members were tested for beta-thalassemia. Carriers of the disease were detected by measuring hemoglobin indices, and amplification refractory mutation system polymerase chain reaction was used for mutation analysis. Genetic counseling was provided to members of this family.

RESULTS

There were already 3 marriages between the carrier members and 1 between a carrier and noncarrier in this large family; 12 (44.4%) members were found to carry the mutant gene, representing a very high carrier rate compared to the 5.4% carrier frequency of beta-thalassemia in the general population of Pakistan. The family was counseled for prevention of affected births. The initially reluctant family gradually became cooperative and seriously attended the genetic counseling sessions.

CONCLUSION

Cascade testing is more practical than general population screening in a country with limited health facilities where consanguineous marriages are practiced. This report emphasizes the need of extensive testing within families with index cases to identify the carriers of beta-thalassemia in order to reduce disease occurrence through awareness and genetic counseling.

Effect of upper- and lower-limb exercise training on circulating soluble adhesion molecules, hs-CRP and stress proteins in patients with intermittent claudication

OBJECTIVES

To investigate the effects of exercise training on levels of circulating biomarkers associated with the progression of atherosclerosis and risk of cardiovascular events in patients with intermittent claudication.

METHODS

Circulating levels of soluble adhesion molecules (sVCAM-1, sICAM-1, sE-selectin), high sensitivity C-reactive protein (hs-CRP) and stress proteins (Hsp60 and Hsp70) in patients randomised to a 24-week programme of arm- or leg-cranking exercise were compared with those in usual care controls.

RESULTS

Arm and leg exercise similarly improved lower-limb aerobic exercise capacity (20% vs 19%, respectively; P<0.001) and maximum walking distance (30% vs 35%, respectively; P<0.001). Improvements in training limb-specific peak oxygen consumption were attenuated for patients in the highest vs lowest quartile for circulating sVCAM-1 levels at baseline (3% vs 25% respectively, P<0.001). Although circulating hs-CRP levels tended to be lower in the arm-cranking group (-1.55 [95% CI: -1.06 to -2.26]mgl(-1)), exercise training had no effect on circulating levels of soluble adhesion molecules or stress proteins.

CONCLUSIONS

These findings suggest that high levels of circulating sVCAM-1 are associated with an attenuated exercise training response and that arm-cranking exercise may provide an effective stimulus for evoking systemic anti-inflammatory adaptations in patients with intermittent claudication.

Prognostic analysis of tumour angiogenesis, determined by microvessel density and expression of vascular endothelial growth factor, in high-risk primary breast cancer patients treated with high-dose chemotherapy

In contrast to early breast cancer, the prognostic effect of tumour angiogenesis in tumours with advanced axillary spread has been less studied. We retrospectively analysed the effect of microvessel density (MVD) and vascular endothelial growth factor (VEGF) by immunohistochemistry on the outcome of 215 patients treated uniformly within prospective trials of high-dose chemotherapy for 4-9 and >/=10 positive nodes, and followed for a median of 9 (range 3-13) years. Microvessel density was associated with epidermal growth factor receptor (EGFR) expression (P<0.001) and tumour size (P=0.001). Vascular endothelial growth factor overexpression (51% of patients) was associated with overexpression of EGFR (P=0.01) and HER2 (P<0.05), but not with MVD (P=0.3). High MVD was associated with worse relapse-free survival (74 vs 44%, P<0.001) and overall survival (76 vs 44%, P<0.001). Vascular endothelial growth factor overexpression had no effect on outcome. Multivariate analyses showed a prognostic effect of MVD independently of other known prognostic factors in this patient population. In conclusion, tumour angiogenesis, expressed as MVD, is a major independent prognostic factor in breast cancer patients with extensive axillary involvement.

Prospective randomized multicentre double-blind placebo-controlled trial of the use of aprotonin in ruptured abdominal aortic aneurysm repair

Background

This study assessed whether the use of aprotonin affects the number of blood products transfused, and the morbidity and mortality rates associated with the repair of a ruptured abdominal aortic aneurysm (AAA).

Methods

Nine centres with local ethics committee approval for the trial were involved in the recruitment of 77 patients. A bolus of either 2 million units of aprotonin, followed by an infusion of 500 000 units every 30 min, or placebo, was prepared and aprotonin was administered to 38 patients, with 39 receiving the placebo. The number of blood products transfused during surgery and in the first 12 h after operation was noted, along with the incidence of complications, mortality rates and length of hospital stay. Analysis of the difference between blood product transfusion was by the Kruskal–Wallis test.

Results

Seventeen of the 38 patients receiving aprotonin and 17 of the 39 given placebo died within 30 days, with an overall mortality rate of 44 per cent. The median amount of blood given to the aprotonin group after operation was 1 (range 0–14) units, while for the placebo group it was 3 (range 0–13) units (P = 0·02). In the aprotonin group, ten patients developed renal failure and ten had respiratory complications. The corresponding figures for the placebo group were nine and 17 respectively. For survivors, the median hospital stay was 12 (range 7–33) days for the aprotonin group and 15 (range 8–52) days for the placebo group.

Conclusion

The use of high-dose aprotonin in ruptured AAA repair leads to less requirement for blood products. It does not appear to affect survival or the incidence of postoperative complications.

Putting your heart into walking further

Background

Leg exercise training improves maximum walking distance (MWD) in claudicants, but it also causes neutrophil activation and may, as a consequence, elicit damage to the coronary circulation. It was hypothesized that symptomatic improvements induced by exercise programmes result from systemic cardiovascular effects rather than localized changes in the lower limb. The aim of this study was to develop an upper body training programme that would enhance cardiovascular fitness while avoiding potentially damaging inflammatory responses.

Methods

Sixty-three stable claudicants were recruited; all underwent arm and leg ergometry exercise assessments. Peripheral blood was obtained before and 1 h after exercise. The intensity (median channel of fluorescence; MCF) of neutrophil CD11b expression (as a measure of neutrophil activation) was determined using whole blood flow cytometry. Patients were randomized to an arm (n = 24) or leg (n = 24) training programme structured to achieve identical heart rate changes. Training involved two supervised sessions per week for 6 weeks. Controls undertook no exercise (n = 15). The MWD was determined at the beginning and end of training.

Results

Arm exercise had no effect on neutrophil expression of CD11b, whereas expression was significantly increased by leg exercise (Table). Arm and leg training increased the maximum work rate from 75 to 100 W (P = 0·004; Wilcoxon test) and there was a concomitant decrease in the submaximal heart rate (arm group 150 to 131 beats min−1; leg group 155 to 136 beats min−1; P = 0·002). These cardiovascular changes were accompanied by an increased MWD (Table). There were no changes in the control group.

Conclusion

Upper body training can increase walking distance in claudicants without neutrophil activation and maximizing cardiovascular fitness appears to be the key to improving symptoms in these patients.

Mesenteric arterial ischaemia: diagnosis and therapeutic options

Ischaemia of the bowel may arise from a number of causes affecting the arterial and venous compartments of the vascular tree. This article addresses the causes and consequences of arterial obstruction, which may compromise the supply of oxygenated blood to the bowel. These events may occur as an acute phenomenon, or they may present in a chronic fashion. The therapeutic options available to treat this condition are largely dependent on the mode of presentation and the amount of time that is available before irreversible damage occurs to the bowel integrity. In the acute phase, the viability of the bowel is in doubt, and this necessitates an open operative approach to assess the amount of bowel infarction which has already occurred. A variety of operative procedures are then available to limit this bowel loss and to secure the viability of the remaining bowel. In the more chronic phase there are alternative, less invasive procedures that may be appropriate for the patient, who may have suffered a prolonged period of undernourishment and dehydration. In such cases the immediate bowel viability is not in doubt, but the medium/long-term survival is compromised. Treatment options appropriate to each clinical scenario are discussed, along with the major technical issues associated with these treatments. A team approach to the most appropriate management plan is stressed, and the published outcomes reviewed.

Albuminuria and risk of cardiovascular events, death, and heart failure in diabetic and nondiabetic individuals

CONTEXT

Microalbuminuria is a risk factor for cardiovascular (CV) events. The relationship between the degree of albuminuria and CV risk is unclear.

OBJECTIVES

To estimate the risk of CV events in high-risk individuals with diabetes mellitus (DM) and without DM who have microalbuminuria and to determine whether levels of albuminuria below the microalbuminuria threshold increase CV risk.

DESIGN

The Heart Outcomes Prevention Evaluation study, a cohort study conducted between 1994 and 1999 with a median 4.5 years of follow-up.

SETTING

Community and academic practices in North and South America and Europe.

PARTICIPANTS

Individuals aged 55 years or more with a history of CV disease (n = 5545) or DM and at least 1 CV risk factor (n = 3498) and a baseline urine albumin/creatinine ratio (ACR) measurement.

MAIN OUTCOME MEASURES

Cardiovascular events (myocardial infarction, stroke, or CV death); all-cause death; and hospitalization for congestive heart failure.

RESULTS

Microalbuminuria was detected in 1140 (32.6%) of those with DM and 823 (14.8%) of those without DM at baseline. Microalbuminuria increased the adjusted relative risk (RR) of major CV events (RR, 1.83; 95% confidence interval [CI], 1.64-2.05), all-cause death (RR, 2.09; 95% CI, 1.84-2.38), and hospitalization for congestive heart failure (RR, 3.23; 95% CI, 2.54-4.10). Similar RRs were seen for participants with or without DM, even after adjusting for other CV risk factors (eg, the adjusted RR of the primary aggregate end point was 1.97 [95% CI, 1.68-2.31] in those with DM and 1.61 [95% CI, 1.36-1.90] in those without DM). Compared with the lowest quartile of ACR (<0.22 mg/mmol), the RRs of the primary aggregate end point in the second quartile (ie, ACR range, 0.22-0.57 mg/mmol) was 1.11 (95% CI, 0.95-1.30); third quartile, 1.38 (95% CI, 1.19-1.60; ACR range, 0.58-1.62 mg/mmol); and fourth quartile, 1.97 (95% CI, 1.73-2.25; ACR range, >1.62 mg/mmol) (P for trend <.001, even after excluding those with microalbuminuria). For every 0.4-mg/mmol increase in ACR level, the adjusted hazard of major CV events increased by 5.9% (95% CI, 4.9%-7.0%).

CONCLUSIONS

Our results indicate that any degree of albuminuria is a risk factor for CV events in individuals with or without DM; the risk increases with the ACR, starting well below the microalbuminuria cutoff. Screening for albuminuria identifies people at high risk for CV events.

The inflammatory response to upper and lower limb exercise and the effects of exercise training in patients with claudication

PURPOSE

We have previously shown that a program of upper limb exercise training can induce significant improvements in walking distance in patients with claudication. This study assessed whether upper limb exercise avoids the systemic inflammatory responses associated with lower limb exercise and also whether the inflammatory response to acute lower limb exertion is modified by a program of supervised exercise training.

METHODS

Fifty-two patients with stable intermittent claudication were randomized into two groups who underwent 6 weeks of supervised upper (n = 26) or lower (n = 26) limb cardiorespiratory exercise training. A parallel control group (n = 15) was provided with lifestyle advice only. Neutrophil activation markers (CD11b and CD66b) and plasma levels of von Willebrand factor (marker of endothelial damage) in response to an acute bout of sustained upper and lower limb exercise were assessed before and after the period of training. Plasma levels of soluble E-selectin (marker of endothelial activation) were also determined before and after the training period.

RESULTS

An acute bout of sustained lower limb exercise significantly increased the intensity of CD11b and CD66b expression by peripheral blood neutrophils in all groups, whereas upper limb exercise had no effect. Resting neutrophil expression of CD11b and CD66b and circulating von Willebrand factor levels were unaffected by the training program, as were the inflammatory responses to an acute bout of sustained upper and lower limb muscular work, despite the fact that both training programs significantly increased walking distances.

CONCLUSIONS

These findings indicate that upper limb exercise training programs may offer certain advantages over currently prescribed lower limb programs. Our results show that exercising nonischemic muscles in a way that promotes improved cardiorespiratory function and walking capacity can avoid the potentially deleterious systemic inflammatory responses associated with lower limb exertion in patients with stable intermittent claudication.