Effect of High Temperature on Reproductive Phase of Plants: A Review

Climate change is a universal challenge that threatens the very existence of life on planet Earth. One of the most sensitive areas to climate change is agriculture. Climate change affects precipitation, cyclones, clouds, temperature, humidity, and CO2 levels. All these factors affect plant productivity which poses another grave concern in feeding the ever-increasing population. The productivity in terms of crop yield is reduced due to a direct correlation between phenology and climate change. The reproductive organs of a plant and other parameters that define good fertility of a species are all affected by the increasing temperatures during their vegetative and reproductive phases of growth and development. Thus, this review is an attempt to understand the effect of climate change on the reproductive structures of plants and discuss the short-term and long-term adaptations in plants and agriculture as mitigation measures to combat the significant yield loss in developing countries.

2213Impact of BMI on clinical outcomes in all-comers patients with coronary artery disease undergoing PCI: insights from the Global Leaders study

Background

It is uncertain if the obesity paradox still exists in contemporary PCI practice.

Purposes

We aimed to assess an association between baseline BMI and clinical outcomes at 2 years after PCI and to determine if the outcomes between two antiplatelet strategies depend on baseline BMI.

Methods

Global Leaders study compared 23-month ticagrelor monotherapy after 1 month of dual antiplatelet therapy (experimental strategy) with 12-month aspirin monotherapy after 12 months of conventional DAPT (reference strategy) in patients undergoing PCI with biolimus-A9 eluting stent.

Primary outcome of current study was 2-year all-cause mortality after PCI. Secondary outcomes were net adverse clinical event (NACE) and individual components of the composite endpoint.

Association between baseline BMI and outcomes were determined in the Cox model. Non-linearity was assessed using restrict cubic spline function. Patients were categorized according to WHO BMI categories; underweight (BMI <18.5), healthy weight (BMI 18.5–24.9), pre-obese state (BMI 25–29.9) and obesity (BMI ≥30). Interaction between BMI categories and antiplatelet strategies were assessed.

Results

BMI was available in 15,966 out of 15,968 patients with a median of 27.7 kg/m2 (IQR 25.0–30.7). Baseline BMI had a reverse J-shaped association with 2-year all-cause mortality. 3901 patients (24.4%) were in the group of healthy weight, 79 patients (0.5%) were under-weight, 7220 patients (45.2%) were pre-obese and 4766 patients (29.8%) were obese. Due to small number of underweight patients, outcomes after PCI were compared among three groups; healthy weight, overweight, and obesity.

Pre-obese and obese patients had lower risk of 2-year all-cause mortality than healthy-weight patients (HR pre-obesity vs. healthy-weight 0.71, 95% CI 0.58–0.88, HR obesity vs. healthy-weight 0.69, 95% CI 0.54–0.87). The risk of 2-year NACE was similar among three groups (healthy weight vs. pre-obesity; HR 1.04, 95% CI 0.94–1.16, healthy weight vs. obesity; HR 1.04, 95% CI 0.93–1.16). No significant difference in risk of any stroke, any MI, and BARC3 or 5 bleeding was found among three groups. Pre-obese patients had higher risk of revascularization than patients with healthy weight (HR 1.19, 95% CI 1.04–1.35). The risk of revascularization in obese patients was numerically higher than healthy-weight patients (HR 1.14, 95% CI 0.99–1.31).

For BARC 3 or 5 bleeding at 2 years, ticagrelor monotherapy was more favorable in obese patients (HR reference/experimental 1.63, 95% CI 1.06–2.52) while conventional DAPT strategy was more favorable in pre-obese patients (HR experimental/reference 0.76, 95% CI 0.55–1.05) (P interaction 0.02). No interaction between treatment strategy, BMI, and other outcomes was seen.

BMI and all-cause mortality and NACE

Conclusions

An obesity paradox, an association between elevated BMI and lower mortality, is still evident in this large PCI population. Effect of two antiplatelet strategies on bleeding may depend on baseline BMI.

Repression of caspase-3 and RNA-binding protein HuR cleavage by cyclooxygenase-2 promotes drug resistance in oral squamous cell carcinoma

A well-studied RNA-binding protein Hu Antigen-R (HuR), controls post-transcriptional gene regulation and undergoes stress-activated caspase-3 dependent cleavage in cancer cells. The cleavage products of HuR are known to promote cell death however, the underlying molecular mechanisms facilitating caspase-3 activation and HuR cleavage remains unknown. Here, we show that HuR cleavage associated with active caspase-3 in oral cancer cells treated with ionizing radiation and chemotherapeutic drug, paclitaxel. We determined that oral cancer cells overexpressing cyclooxygenase-2 (COX-2) limited the cleavage of caspase-3 and HuR, which reduced the rate of cell death in paclitaxel resistant oral cancer cells. Specific inhibition of COX-2 by celecoxib, promoted apoptosis through activation of caspase-3 and cleavage of HuR in paclitaxel-resistant oral cancer cells, both in vitro and in vivo. In addition, oral cancer cells overexpressing cellular HuR increased the half-life of COX-2 mRNA, promoted COX-2 protein expression and exhibited enhanced tumor growth in vivo in comparison with cells expressing a cleavable form of HuR. Finally, our ribonucleoprotein immunoprecipitation and sequencing (RIP-seq) analyses of HuR in oral cancer cells treated with ionizing radiation (IR), determined that HuR cleavage product-1 (HuR-CP1) bound and promoted the expression of mRNAs encoding proteins involved in apoptosis. Our results indicated that, cellular non-cleavable HuR controls COX-2 mRNA expression and enzymatic activity. In addition, overexpressed COX-2 protein repressed the cleavage of caspase-3 and HuR to promote drug resistance and tumor growth. Altogether, our observations support the use of the COX-2 inhibitor celecoxib, in combination with paclitaxel, for the management of paclitaxel resistant oral cancer cells.

Impact of proctoring on success rates for percutaneous revascularisation of coronary chronic total occlusions

OBJECTIVE

To assess the impact of proctoring for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in six UK centres.

METHODS

We retrospectively analysed 587 CTO procedures from six UK centres and compared success rates of operators who had received proctorship with success rates of the same operators before proctorship (pre-proctored) and operators in the same institutions who had not been proctored (non-proctored). There were 232 patients in the pre-proctored/non-proctored group and 355 patients in the post-proctored group. Complexity was assessed by calculating the Japanese CTO (JCTO) score for each case.

RESULTS

CTO PCI success was greater in the post-proctored compared with the pre-proctored/non-proctored group (77.5% vs 62.1%, p<0.0001). In more complex cases where JCTO≥2, the difference in success was greater (70.7% vs 49.5%, p=0.0003). After proctoring, there was an increase in CTO PCI activity in centres from 2.5% to 3.5%, p<0.0001 (as a proportion of total PCI), and the proportion of very difficult cases with JCTO score ≥3 increased from 15.3% (35/229) to 29.7% (105/354), p<0.0001.

CONCLUSIONS

Proctoring resulted in an increase in procedural success for CTO PCI, an increase in complex CTO PCI and an increase in total CTO PCI activity. Proctoring may be a valuable way to improve access to CTO PCI and the likelihood of procedural success.

Successful autotransplantation of a mature mesiodens to replace a traumatized maxillary central incisor

AIM

This case describes the successful transplantation of a mature mesiodens tooth to replace a traumatized maxillary central incisor.

SUMMARY

A 17-year-old male attended 1 week after a traumatic injury to his left maxillary central incisor (tooth 21). Radiographs revealed a horizontal root fracture and a poor prognosis. The tooth was atraumatically removed and replaced with a mesiodens lying in the same region. After stabilization, root canal treatment was performed and aesthetics were restored with a tooth coloured restoration. A 2-year follow-up revealed the tooth had good aesthetics and function.

KEY LEARNING POINTS

A supernumerary nonfunctional tooth such as a mesiodens can be successfully used to replace a missing permanent tooth by autotransplantation. Autotransplantation has a high success rate if case selection is good, appropriate surgery is carried out and excellent hygiene is maintained. Autotransplantation should be considered as one of the most biologic techniques for replacing a missing tooth with minimal cost. Autotransplantation can be carried out even after complete root formation in the donor tooth.

A laboratory comparison of apical leakage between immediate versus delayed post space preparation in root canals filled with Resilon

AIM

To analyse ex vivo the integrity of the apical seal of Resilon root fillings following immediate post space preparation or after 1 week when leaving either 5 mm or 3 mm of remaining filling material.

METHODOLOGY

One hundred and fifty freshly extracted mandibular premolar teeth with single, straight root canals were used. Teeth were autoclaved and cleaned of debris and soft tissue. After decoronation at 16 mm length, the root canals were instrumented using the K3 rotary system to apical file size 45, 0.04 taper with intermittent irrigation using 1% sodium hypochlorite. The teeth were randomly divided into five groups with 30 teeth in each group. Group 1: control group in which the root canals were not filled. Group 2: the canals were filled with Resilon and a post space prepared immediately leaving 5 mm of apical filling. Group 3: the canals were filled and post space preparation delayed for 1 week leaving 5 mm of material apically. Group 4: post space preparation in the canals was initiated immediately after filling leaving 3 mm of material apically. Group 5: the root canals were filled and post space preparation was delayed for 1 week leaving 3 mm of material apically. Microleakage was evaluated using a fluid transport device. The results were analysed statistically using one-way anova followed by Bonferroni's post hoc test. P < 0.05 was considered as statistically significant.

RESULTS

There was a highly significant difference amongst the groups (P < 0.001). The maximum mean leakage was observed in group 5 (141.63 x 10(-6) microL min(-1) cm(-1)) and the least microleakage in group 2 (99.87 x 10(-6) microL min(-1) cm(-1)).

CONCLUSION

Immediate post space preparation was associated with less microleakage than delayed preparation when both 5 mm and 3 mm of apical filling remained. Leaving 5 mm of Resilon provided a significantly better seal compared to leaving 3 mm of material.

Influence of activating and inhibitory killer immunoglobulin-like receptors on predisposition to recurrent miscarriages

BACKGROUND

Understanding of the immune events and mechanisms occurring at the feto-maternal interface is likely to help in understanding the ability of the fetus to survive within the maternal body. Evidence supporting extensive roles of natural killer cells during pregnancy gives rise to a possibility that these NK cells can be mis-regulated and involved in fetal allograft rejection. Killer immunoglobulin-like receptors (KIR) play an important role in regulating the NK cell activity through their activating and inhibiting isoforms. Since there exists a considerable, genetically determined variation in the repertoire of KIR receptors between different individuals, a particular maternal KIR repertoire may predispose to recurrent miscarriages (RMs).

METHODS

Gene-specific PCR amplification (PCR-SSP) was used to determine the individual KIR genotypes in women experiencing RM and controls.

RESULTS

A higher prevalence of activating KIR genes was seen in patients than in controls. Among women experiencing RM, the BB genotypes were more prevalent (P < 0.0001, OR = 4.4, 95% CI = 2.89-6.69) compared with controls.

CONCLUSIONS

Our results indicate that the balance between inhibitory and activating receptor-mediated signals present in natural killer cells is inclined toward a more activating state that may contribute to pregnancy loss.

Chimerism monitoring following allogeneic hematopoietic stem cell transplantation

Information regarding the chimeric status of hematopoietic stem cell transplantation (HSCT) recipients is of great significance when comparing different conditioning and prophylactic therapies. In recent years, short tandem repeats/variable number tandem repeats (STRs/VNTRs) have emerged as the best tool for chimerism monitoring. However, the polymorphisms of STR/VNTR markers vary within and between ethnic groups. The issue is further complicated in a heterogeneous population such as occurs in the Indian subcontinent. In the present study, we attempted to devise a robust scheme to identify a set of polymorphic STRs/VNTRs most suitable for chimerism evaluation in north Indian HCST recipients. At first, we did genotyping of 11 STR and one VNTR in 1000 randomly chosen north Indian individuals to quantify different diversity parameters. Resulting data indicated that ApoB3'HVR, FES, VWA, D3S1358 and D16S310 were most polymorphic loci with the average heterozygosity being 0.756+/-0.17. Furthermore, all markers were genotyped in 77 HLA-matched donor-recipient pairs to evaluate the informativeness in differentiating donor's and recipient's cells. A panel of seven markers (ApoB3HVR-D3S1358-HUM-THO1-VWF-1-D16S310-FES-VWA) differentiated 98.70% of donor-recipient pairs. This set of markers also successfully monitored the graft status in 14 HSCT cases during multiple time points following HSCT. The results were compared to the commercially available AmpF/STR SGM Plus multiplex PCR kit (Applied Biosystems, Foster City, CA, USA). Our findings established that the panel of seven markers we identified was more cost-effective and informative.

Disease progression and adverse events in patients listed for elective percutaneous coronary intervention

OBJECTIVE

To record disease progression and the timing of adverse events in patients on a waiting list for elective percutaneous coronary intervention (PCI).

DESIGN

Observational prospective study.

SETTINGS

A UK tertiary cardiothoracic centre, at a time when waiting lists for PCI were up to 18 months.

PATIENTS

145 patients (116 men, median age 59.5 years) placed on an elective waiting list for PCI between October 1998 and September 1999.

MAIN OUTCOME MEASURES

Adverse events recorded were death, myocardial infarction, need for urgent hospital admission because of unstable angina, and need for emergency revascularisation while waiting for PCI.

RESULTS

During a median follow up of 10 months (range 1-18 months), nine (6.2%) patients experienced an adverse event. Eight (5.52%) patients were admitted with unstable angina as emergencies. One was admitted with a myocardial infarction. Twenty nine (20.0%) patients had significant disease progression at the time of the repeat angiogram before PCI. In 10 (7%), disease had progressed so that PCI was no longer feasible and patients were referred for coronary artery bypass graft. Sixteen (11%) were removed from the PCI waiting list because of almost complete resolution of their anginal symptoms.

CONCLUSION

Adverse coronary events and clinically significant disease progression occur commonly in patients waiting for PCI. Despite the presence of severe coronary lesions, myocardial infarction was rare and no patients died while on the waiting list. Resolution of anginal symptoms was also comparatively common. The pathophysiology of disease progression frequently necessitates a change in the treatment of patients waiting for PCI.

Tubercular pseudoaneurysms of aorta

BACKGROUND

Tubercular pseudoaneurysm of aorta is a rare but important complication of tuberculosis. With worldwide resurgence of tuberculosis due to increasing incidence of drug-resistant tuberculosis and its association with acquired immunodeficiency syndrome, the tubercular pseudoaneurysm has become a real clinical entity.

METHODS

In the past 3 years, 5 young patients (22 to 40 years) presented with tubercular pseudoaneurysm. Site of involvement included ascending aorta, distal aortic arch, proximal descending thoracic aorta, distal descending thoracic aorta, and infrarenal abdominal aorta. Two patients had macroscopic focus of tuberculosis in the nearby vicinity, and all 5 patients had evidence of active/treated pulmonary pericardial tuberculosis. All patients either had received antitubercular therapy previously or were receiving it at the time of presentation. Rapid deterioration in the clinical status was the most marked clinical feature. All patients underwent operation. Graft interposition was performed in 2, patch repair in 2, and direct closure of the rent was performed in 1 patient. All 5 patients received antitubercular therapy in the postoperative period.

RESULTS

All patients survived the operation and were discharged from the hospital. One patient developed recurrence at the original site after 8 months and died at reoperation. The remaining patients are symptom free at 18 to 36 months postoperatively.

CONCLUSIONS

A combination of chemotherapy and operation yields gratifying results for the treatment of tubercular pseudoaneurysm.

Fate of mild aortic valve disease after mitral valve intervention

OBJECTIVE

This study was performed to assess the long-term outcome of untreated mild aortic valve disease present at the time of initial mitral valve intervention.

METHODS

A total of 284 patients with rheumatic heart disease aged 7 to 62 years (mean, 23.5 +/- 12.2 years) who underwent mitral valve intervention and had mild aortic valve disease initially were followed up for 2 to 18 years (mean, 10.8 +/- 3.7 years). At initial intervention, 232 patients had pure mild aortic regurgitation, and 52 patients had mild aortic stenosis with or without aortic regurgitation.

RESULTS

Among patients with mild aortic regurgitation initially, 11 (5%) patients progressed to moderate (n = 6) or severe (n = 5) regurgitation over an interval of 9 to 17 years (mean, 12.1 +/- 2.8 years), and 1 patient had moderate aortic stenosis and severe aortic regurgitation after 10 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic regurgitation was 100%, 97.0% +/- 1.7%, and 87.4% +/- 4.6% at 5, 10, and 15 years, respectively. Seventeen (35%) patients with initial mild aortic stenosis (with or without regurgitation) had moderate or severe stenosis (with or without moderate-severe regurgitation) after an interval of 4.9 +/- 3.8 years. Freedom from development of moderate-severe aortic valve disease in patients who initially had mild aortic stenosis was 75.6% +/- 6.2%, 61.5% +/- 8.5%, and 46.1% +/- 11.2% at 5, 10, and 15 years, respectively. Ten patients required aortic valve replacement for aortic valve dysfunction.

CONCLUSIONS

Mild aortic regurgitation present at the time of mitral valve intervention progresses very slowly and less frequently requires reintervention. However, mild aortic stenosis diagnosed initially progresses more often and more rapidly and thus needs closer follow-up.

Omentopexy for limb salvage in Buerger's disease: indications, technique and results

Buerger's disease is a limb-threatening condition occurring in the young and productive age group and its management has always been a challenging problem. A large number of medical and surgical options have been suggested, but the quest for an ideal solution to this problem continues. Omentopexy for Buerger's disease is an attractive option, which is rapidly gaining popularity. We discuss the historical aspects, technical considerations and results of omental transfer for this limb-threatening condition. In doing so, the relevant literature on the subject has been extensively reviewed. In all published series, there has been marked improvement in intermittent claudication and rest pain. Ischaemic ulcers have healed and the progression of gangrene has stopped. If carried out with the complete understanding of the anatomy of the omental vascular arcade, the results of omentopexy are gratifying, thus avoiding amputation and conserving the limb.

Single-stage lumbar sympathectomy and omentopexy: a new surgical approach towards patients with Buerger's disease

Single-stage lumbar sympathectomyand omentopexy were performed in six patients with Buerger's disease at the Department of Surgery, Jawahar Lal Nehru Medical College and Hospital, Ajmer, India, between January 1994 and December 1996. All were male smokers and had limb coldness, intermittent claudication and rest pain. Four had limb discoloration and three had ulcers of toes unresponsive to medical treatment. Postoperatively there was relief of symptoms in all, with improvement of tissue oxygen saturation and increase in claudication distance. We conclude that single-stage lumbar sympathectomy and omentopexy is an effective new surgical approach towards patients with Buerger's disease.

Prolonged stability of endogenous cardiotrophin-1 in whole blood

Cardiotrophin-1 (CT-1) is a recently identified cytokine of the interleukin-6 (IL-6) family that signals through the gp130 signalling pathway. CT-1 may be of central importance to the pathogenesis of ventricular remodelling in patients with acute myocardial infarction (AMI) and therefore have clinical value in the identification of patients with impaired ventricular function. Central to the clinical use of CT-1 is in the in vitro stability of the peptide. Twelve subjects were recruited. A total of 25 mL of peripheral venous blood was collected into chilled polypropylene tubes containing EDTA and aprotinin and divided into 5 aliquots. One sample was spun in a prerefrigerated centrifuge (4 degrees C) at 3,000 rpm for 10 minutes and plasma separated and frozen at -70 degrees C immediately. Remaining samples were stored for 24 and 48 hours at room temperature or on ice. CT-1 in extracted plasma specimens was measured with a competitive chemiluminescent assay. The concentration of CT-1 in samples stored optimally was 43.1 +/- 6.05 fmol/mL. CT-1 levels for storage at room temperature compared with ice at the remaining time points were as follows: 24 hours, 41.5 +/- 5.76 v 37.5 +/- 8.66; and 48 hours, 42.6 +/- 6.28 v 41.0 +/- 5.42 fmol/mL. There were no significant changes in concentrations of CT-1 stored optimally or kept for up to 48 hours in aliquots of whole blood at room temperature or on ice. We conclude that CT-1 is stable in specimens of whole blood treated with EDTA and aprotinin and stored for up to 48 hours at room temperature or on ice, hence permitting its development in the routine clinical investigation of patients with heart failure.

Mitral valve repair in a predominantly rheumatic population. Long-term results

Valve repair in rheumatic patients poses special problems due to valve deformity and mixed lesions. We present our experience from January 1988 through June 1999, in this retrospective study of 818 patients (377 males). The mean age was 22.8 +/- 11.3 years (range, 2 to 70 years). The cause of mitral regurgitation was rheumatic in 718 (88%) patients, congenital in 51, myxomatous in 34, infective in 7, and ischemic in 8. Most patients (64%) were in New York Heart Association functional class III or IV. Congestive heart failure was present in 116 patients (14%). Reparative procedures included posterior collar annuloplasty (n=710), commissurotomy (n=482), cusp-level chordal shortening (n=237), cusp thinning (n=222), cleft suture (n= 166), and cusp excision/plication (n=42). Operative mortality was 4% (32 patients). Preoperative left ventricular dysfunction, presence of congestive heart failure, and advanced functional class were associated with greater mortality. Follow-up ranged from 1 to 144 months (mean, 44.9 +/- 33.2 months) and was 96% complete. Most survivors (70%) had no or trivial mitral regurgitation. Forty patients required reoperation for valve dysfunction. There were 23 (2.8%) late deaths. Actuarial, reoperation-free, and event-free survival at 11 years were 92.6% +/- 1.0%, 65.0% +/- 10%, and 38% +/- 6.0%, respectively Among the survivors, 85% were in New York Heart Association functional class I. We conclude that mitral valve repair in rheumatic patients, using current techniques, can effectively correct hemodynamic and functional abnormalities with satisfactory results.

Subaortic membrane excision: Mid-term results

BACKGROUND

Subaortic membrane (SAM) is a form of fixed subaortic obstruction in which a fibrous membrane is located below the aortic valve.

AIM

To determine the role of surgical treatment for patients with a discrete SAM.

PATIENTS AND METHODS

The hospital records of 45 patients (age range: 2-23 years; median 8 years) undergoing surgery for SAM between 1990 and 1998 at the All India Institute of Medical Sciences, New Delhi, India, were analysed. Preoperative echocardiographically calculated gradients across the left ventricular outflow tract ranged from 50 to 154 mmHg (mean: 86.5 +/- 33.2 mmHg). Nine patients had trivial aortic regurgitation (AR), 10 had mild AR and five had moderate-severe AR. The left ventricular ejection fraction (LVEF) ranged from 20 to 68% (mean 48 +/- 15%). Nineteen patients had significant left ventricular dysfunction (LVEF <50%). Transaortic resection of SAM was done in all patients along with excision of a wedge-shaped segment of septal muscle underlying the membrane.

RESULTS

There were no early or late postoperative deaths. On follow up (up to 113 months), only four patients had gradients >30 mmHg. LVEF improved to 45-70% (mean 58 +/- 7.7%). AR reduced to mild in four patients and trivial in four patients, and did not progress further.

CONCLUSION

Resection of SAM carries long-term benefits. Routine septal myectomy appears to be associated with a low risk of recurrence.

Plasma N-terminal pro BNP and cardiotrophin-1 are elevated in aortic stenosis

BACKGROUND

Echocardiography with Doppler examination of the aortic valve provides a very accurate assessment of the transvalvular gradient and is used to monitor progression of aortic stenosis (AS). Plasma brain natriuretic peptide (BNP) has been shown to correlate with end-systolic wall stress in patients with AS.

AIM

We hypothesized that plasma N-terminal proBNP (NT proBNP) and a newly identified cytokine cardiotrophin-1 (CT-1), which has been shown to stimulate BNP production at a transcriptional level are elevated in patients with AS and correlate to the maximum trans-valvular aortic pressure gradient (TVPG).

METHOD

We compared plasma NT proBNP and CT-1 in 15 AS patients [five males, mean age 79 years [range 60-94], mean TPVG 39.3 mmHg (20-100)] with 10 controls (five male, mean age 68 years [56-79]). Results are expressed as mean [ranges] and comparisons were by the Mann-Whitney test.

RESULTS

NT proBNP levels were elevated in AS patients [252.9 fmol/ml (79.2-541.8)] when compared with the controls (157.2 fmol/ml [104.7-236.9], P<0.005). Also CT-1 levels were elevated in AS patients (57.3 fmol/ml [33-86.3] when compared with the controls [28.3 fmol/ml (6.9-48.3), P<0.0005]. Both NT proBNP and CT-1 levels were correlated to the TVPG (r=0.53 and r=0.65, P<0.05 and P=0.009, respectively). On best subset analysis the strongest correlate with TVPG was CT-1 (R2=38%). The addition of NT proBNP did not improve diagnostic accuracy (R2=39%).

CONCLUSION

These results suggest NT proBNP and CT-1 levels increase in proportion to the TVPG and could potentially be used to monitor progression of disease non-invasively. These markers may also be useful to identify the optimum time for surgery in AS.

Cardiotrophin-1 protects the human myocardium from ischemic injury. Comparison with the first and second window of protection by ischemic preconditioning

BACKGROUND

There are reports suggesting that cardiotrophin 1 (CT-1) is cytoprotective. We investigated the cardioprotective effects of CT-1 on the human myocardium and compared this benefit with the early and delayed protection afforded by ischemic preconditioning (PC).

METHODS

Right atrium specimens were prepared and incubated in buffer solution at 37 degrees C for 30 min stabilisation, before entering one of the three following studies. In study 1, muscles (n=6/group) were allocated to one of four groups: (i) aerobic control - incubated in oxygenated media for 210 min, (ii) ischemia alone - 90 min ischemia followed by 120 min reoxygenation, (iii) PC by 5 min ischemia-5 min reoxygenation before 90 min ischemia-120 min reoxygenation and (iv) CT-1 (1 nM) - 90 min ischemia-120 min reoxygenation with exposure to CT-1 throughout the protocol. In study 2, muscles (n=6/group) were allocated to one of four protocols as in study 1with the exception that were incubated for 24 h followed by 30 or 90 min ischemia-120 min reoxygenation on day 2. In study 3, the same groups were employed as in study 2 with the exception that only a 30-min period of ischemia was used and that CT-1 antibody (5 microg/ml) was added to all groups throughout the experimental protocol. Creatine kinase (CK, U/g wet wt.) leakage into the medium and MTT reduction (OD/mg wet wt.), an index of cell viability, were assessed at the end of the experiment.

RESULTS

In study 1, a first window of cardioprotection was observed with PC (CK=4.39+/-0.34; MTT=0.58+/-0.03 vs. CK=7.11+/-0.4;MTT=0.32+/-0.02 in the ischemic alone group; P<0.001) but not with CT-1(CK=6.65+/-0. 67; MTT=0.31+/-0.03, P=NS vs. ischemia alone). In study 2, PC applied on day 1 was protective against 30-min ischemia (CK=3.28+/-0. 43; MTT=0.68+/-0.046, P<0.001 vs. ischemia alone) but not against 90-min ischemia (CK=7.13+/-0.66; MTT=0.24+/-0.03, P=NS vs. ischemia alone) induced on day 2 (second window). However, when the tissue was exposed to CT-1 for 24 h, protection was similar to that of PC when subjected to 30 min of ischemia (CK=2.95+/-0.71; MTT=0.77+/-0. 05, P=NS vs. PC) and greater than PC when subjected to 90 min of ischemia (CK=4.56+/-0.51; MTT=0.39+/-0.03, P=0.002 vs. PC). In study 3, the CT-1 antibody did not affect the protection induced by PC (CK=3.36+/-0.6; MTT=0.69+/-0.06) but it abolished the protection obtained with CT-1(CK=5.15+/-0.81; MTT=0.42+/-0.06, P=NS vs. ischemia alone group).

CONCLUSIONS

CT-1 exhibits a significant protection of the human myocardium against ischemic injury when tissue is exposed to this factor for a long period (e.g. 24 h) but not when exposed for a short period (e.g. 2 h). In addition, the protection afforded by long exposure to CT-1 is as potent or even greater than the one obtained by the second window of PC. The protection induced by CT-1 but not that induced by PC can be abolished by CT-1 antibody suggesting that their beneficial action is attained by different mechanisms.

The effect of valvular regurgitation on plasma Cardiotrophin-1 in patients with normal left ventricular systolic function

BACKGROUND

Cardiotrophin-1 (CT-1), a member of the interleukin-6 related cytokine family that act via the gp130 signalling pathway, has been shown to stimulate the assembly of sarcomeric units in series in cardiomyocytes resulting in eccentric hypertrophy, ventricular dilatation and finally loss of function. In situations of volume overload a similar form of eccentric hypertrophy occurs with time.

AIMS

We hypothesised that plasma CT-1 would be raised in patients with significant mitral, tricuspid and/or aortic regurgitation (MR/TR or AR, respectively) when compared to those with no (or mild) valvular regurgitant lesion.

METHODS

A novel competitive immunoluminometric assay using an in-house polyclonal antibody to amino acids 105-120 of the CT-1 sequence was developed. Seventy-eight patients (31 male, mean+/-S.D. age 63.5+/-17.9 years), all with normal left ventricular systolic function were studied. Results are expressed as mean+/-S.D. fmol/ml.

RESULTS

Sixty-three subjects had no significant valvular lesion, seven had moderate/severe MR, nine had moderate/severe TR and four had moderate/severe AR. These subjects had CT-1 concentrations of 53. 3+/-23.2, 90.5+/-44.4, 72.6+/-43.8 and 48.4+/-24.4, respectively (P=0.02, ANOVA). Mean log CT-1 was higher in those with moderate/severe MR when compared to those without a significant regurgitant valvular lesion (P<0.03). The only predictor of moderate/severe MR was log CT-1 (P=0.004).

CONCLUSION

These results suggest that plasma CT-1 is raised in those patients with moderate/severe MR in the presence of normal left ventricular systolic function. This secretion of CT-1 could potentially be the cause of ventricular dilatation and subsequent loss of contractile function in these patients. It also offers the intriguing possibility that plasma CT-1 could be used to monitor progression of mitral regurgitation biochemically.

Plasma N terminal pro-brain natriuretic peptide and cardiotrophin 1 are raised in unstable angina

OBJECTIVE

To compare circulating concentrations of N terminal pro-brain natriuretic peptide (N-BNP) and cardiotrophin 1 in stable and unstable angina.

DESIGN AND SETTING

Observational study in a teaching hospital.

PATIENTS

15 patients with unstable angina, 10 patients with stable angina, and 15 controls.

MAIN OUTCOME MEASURES

Resting plasma N-BNP and cardiotrophin 1 concentrations.

RESULTS

N-BNP concentration (median (range)) was 714 fmol/ml (177-3217 fmol/ml) in unstable angina, 169.5 fmol/ml (105.7-399.5 fmol/ml) in stable angina (p = 0.005 v unstable angina), and 150.5 fmol/ml (104. 7-236.9 fmol/ml) in controls (p < 0.0001 v unstable angina; NS v stable angina). Cardiotrophin 1 concentration was 142.5 fmol/ml (42. 2-527.4 fmol/ml) in unstable angina, 73.2 fmol/ml (41.5-102.1 fmol/ml) in stable angina (p < 0.05 v unstable angina), and 27 fmol/ml (6.9-54.1 fmol/ml) in controls (p < 0.0005 v stable angina; p < 0.0001 v unstable angina). Log cardiotrophin 1 correlated with log N-BNP in unstable angina (r = 0.93, p < 0.0001).

CONCLUSIONS

Both circulating N-BNP and cardiotrophin 1 are raised in unstable angina, while cardiotrophin 1 alone is raised in stable angina. The role of cardiotrophin 1 and the relation between cardiotrophin 1 and N-BNP in myocardial ischaemia remain to be defined.

Profile of plasma N-terminal proBNP following acute myocardial infarction; correlation with left ventricular systolic dysfunction

AIMS

The aims of this study were to describe the temporal pattern of plasma N-terminal pro-brain natriuretic peptide, to examine the optimum time of sampling and to compare plasma N-terminal pro-brain natriuretic peptide to clinical criteria in terms of identification of impaired left ventricular systolic function following acute myocardial infarction.

METHODS AND RESULTS

Measurements of N-terminal pro-brain natriuretic peptide were made in 60 patients at 14-48 h, 49-72 h, 73-120 h, 121-192 h following myocardial infarction and at 6 weeks in survivors. Left ventricular wall motion index was assessed during hospitalization (WMI-1) and at 6 weeks (WMI-2). N-terminal pro-brain natriuretic peptide levels were elevated at all time points, to a greater extent in anterior compared to inferior infarction (P < 0.05). A biphasic profile of plasma concentration was observed in anterior infarction with peaks at 14-48 h and 121-192 h. This was sustained at 6 weeks. N-terminal pro- brain natriuretic peptide at 73-120 h was the best independent predictor of WMI-1 (P < 0.005). N-terminal pro-brain natriuretic peptide was higher at all times in patients who received ACE inhibitor therapy compared to those who did not (P < 0.005). N-terminal pro-brain natriuretic peptide at 73-120 h (R(2) = 17.7%, P = 0.005) and previous myocardial infarction (R(2) = 5.3%, P < 0.05) were independent predictors of poor outcome (WMI-2 < or = 1.2 or death by 6 weeks).

CONCLUSIONS

A biphasic pattern of plasma N-terminal pro-brain natriuretic peptide is seen after anterior myocardial infarction. Plasma level is strongly correlated to wall motion index soon after and remote from acute myocardial infarction. Plasma N-terminal pro-brain natriuretic peptide measured later in hospitalization better predicts poor outcome following myocardial infarction than when it is measured in the immediate post infarction period.

Elevated circulating cardiotrophin-1 in heart failure: relationship with parameters of left ventricular systolic dysfunction

Cardiotrophin-1 (CT-1) is a cytokine that has been implicated as a factor involved in myocardial remodelling. The objective of the present study was to establish the relationship between circulating levels of CT-1 and measures of left ventricular size and systolic function in patients with heart failure. We recruited 15 normal subjects [six male; median age 60 years (range 30-79 years)] and 15 patients [11 male; median age 66 years (range 43-84 years)] with a clinical diagnosis of heart failure and echocardiographic left ventricular systolic dysfunction (LVSD). Echocardiographic variables (left ventricular wall motion index, end-diastolic and -systolic volumes, stroke volume, fractional shortening) and plasma CT-1 levels were determined. In patients with LVSD [median wall motion index 0.6 (range 0.3-1.4)], CT-1 was elevated [median 110.4 fmol/ml (range 33-516 fmol/ml)] compared with controls [wall motion index 2 in all cases; median CT-1 level 34.2 fmol/ml (range 6.9-54.1 fmol/ml); P<0.0001]. Log CT-1 was correlated with log wall motion index (r=-0.76, P<0.0001), log left ventricular end-systolic volume (r=0.54, P<0.05), stroke volume (r=-0.60, P=0.007) and log fractional shortening (r=-0.70, P=0.001). In a multivariate model of the predictors of log wall motion index, the only significant predictor was log CT-1 (R(2)=56%, P=0.006). This is the first assessment of the relationship between plasma CT-1 levels and the degree of LVSD in humans, and demonstrates that CT-1 is elevated in heart failure in relation to the severity of LVSD.

Influence of hypertension, left ventricular hypertrophy, and left ventricular systolic dysfunction on plasma N terminal proBNP

OBJECTIVES

To examine the relation between plasma concentration of the N terminal of the precursor of brain natriuretic peptide (NT proBNP), left ventricular hypertrophy (LVH), and left ventricular systolic dysfunction (LVSD) in patients with a history of hypertension.

DESIGN

Prospective study.

SETTING

Teaching hospital based study.

PATIENTS

NT proBNP concentrations were determined in five groups of individuals. Group 1: 15 echocardiographic normal controls; group 2: 22 patients with hypertension, normal left ventricular systolic function, and no LVH; group 3: 24 patients with hypertension, normal left ventricular systolic function, and LVH; group 4: 13 patients with history of hypertension, no history of ischaemic heart disease, and left ventricular wall motion index (WMI) between 1.9-1.3; and group 5:17 patients with a history of hypertension, no history of ischaemic heart disease, and WMI < 1.2.

RESULTS

Median (range) NT proBNP concentrations (in fmol/ml) for groups 1-5, respectively, were: 129.4 (53.6-159.7), 147.4 (54.3-730. 5), 137.1 (35.8-403.9), 356.7 (124.4-934.4), and 493.5 (248.9-909). Mean log NT proBNP differed among all five groups (p < 0.0001), and between groups 4 and 5 versus groups 1-3 (p < 0.0001), and group 4 versus group 5 (p = 0.02) only.

CONCLUSIONS

The results suggest that the presence of hypertension with or without LVH (and normal left ventricular systolic function) does not affect NT proBNP concentrations. Moreover, there is a significant rise in NT proBNP only when LVSD develops in hypertension. Thus, NT proBNP remains a useful diagnostic aid for LVSD, even in hypertensive patients.

Pedicled omental transfer for limb salvage in Buerger's disease

We performed pedicled omental transfer in 62 patients with Buerger's disease at the Department of Surgery, J.L.N. Hospital, Ajmer between January 1990 and December 1996. All were male and had evidence of limb ischaemia. Post-operative results in these patients consisted of relief of intermittent claudication in 92%, disappearance of rest pain in 94%, disappearance of limb coldness in 83%, disappearance of discolouration in 82%, and healing of ischaemic ulcers in 83%. Tissue oxygen saturation in the affected limb improved from a mean of 84.8+/-3.6% in the preoperative period, to 89+/-1.5% at 12 h, 93.1+/-1.8% at 72 h and 96+/-1.2% at the end of 2 months of follow-up. Claudication distance improved from a mean of 75+/-20 m in the pre-operative period to 1000+/-110 m at 2 months of follow-up in 57 of 62 patients. Major amputations were not required in any patient, thus conserving the limb. We conclude that pedicled omental transfer offers promising results in patients with limb ischaemia due to Buerger's disease.

Bentall operation with valved homograft conduit

Lesions of the ascending aorta associated with aortic valve disease are usually treated by implanting a prosthetic valved conduit (Bentall procedure). In this report, we present our experience in which a valved homograft conduit was used for the procedure. Six patients underwent a Bentall procedure with the use of a cryopreserved valved homograft conduit. Two of the patients had annuloaortic ectasia, 2 had Marfan syndrome, and 1 had an atherosclerotic aneurysm of the aorta. One patient had severe aortic stenosis due to a bicuspid aortic valve, along with an aneurysm and localized dissection of the ascending aorta. In all of the patients, the aortic annulus was substantially dilated, with accompanying moderate-to-severe aortic regurgitation. A standard procedure was performed with moderate hypothermia, cardiopulmonary bypass, and aortic and bicaval cannulation. The ascending aorta and the aortic valve were replaced with a cryopreserved valved homograft conduit (aortic in 5 patients and pulmonary in 1). The native coronary ostia were anastomosed directly to the homograft. Echocardiography, which was performed intraoperatively, before discharge from the hospital, and at follow-up visits (1 to 36 months), revealed good valve function without dilatation of the homograft conduits. There was 1 late death due to Aspergillus fumigatus endocarditis, 6 months postoperatively. In 1 patient, magnetic resonance imaging performed at 24 months revealed normal caliber of the homograft conduit. We conclude that the Bentall procedure can be performed, safely and with excellent results, using cryopreserved homograft conduits.

Plasma N-terminal pro-brain natriuretic peptide and the ECG in the assessment of left-ventricular systolic dysfunction in a high risk population

AIMS

To examine the value of N-terminal pro-brain natriuretic peptide, abnormal electrocardiogram and other baseline clinical and laboratory variables in identifying patients with left ventricular systolic dysfunction in a high risk population.

METHODS AND RESULTS

We studied 243 patients (129 male, median age 73 years, range 20-94) referred for echocardiography. The relationship between left ventricular wall motion index and log N-terminal pro-brain natriuretic peptide, log creatinine, electrocardiogram, age, history of hypertension, history of ischaemic heart disease, gender, valvular disease and current drug therapy was examined using regression analysis. There was a strong correlation between N-terminal pro-brain natriuretic peptide and left ventricular wall motion index for the whole population (r=-0.624, P<0.001) and in those receiving diuretic +/- angiotensin converting enzyme inhibitor (r= -0.661, P<0.005) and in those receiving neither (r=-0.584, P<0. 005). On multiple regression analysis, log N-terminal pro-brain natriuretic peptide (P<0.001), age (P=0.015), current diuretic (P=0. 002) or angiotensin converting enzyme inhibitor use (P=0.001) and male gender (P=0.026) were independently associated with a low left ventricular wall motion index. Log N-terminal pro-brain natriuretic peptide alone (R(2)=39%) was a better predictor of left ventricular wall motion index than any other single or combination of factors. Plasma N-terminal pro-brain natriuretic peptide>275 pmol l(-1)predicted left ventricular wall motion index < or =1.2 with a sensitivity of 93.8%, a specificity of 55% and a negative predictive value of 93%. Left ventricular function was impaired in 18/36 patients with a normal electrocardiogram, in all of whom N-terminal pro-brain natriuretic peptide was >275 fmol ml(-1).

CONCLUSION

Of the variables studies, N-terminal pro-brain natriuretic peptide had the strongest correlation with reduced left ventricular wall motion index. The electrocardiogram had a poor predictive value for left ventricular systolic dysfunction in this population. Plasma N-terminal pro-brain natriuretic peptide can usefully predict patients with a reduced left ventricular wall motion index in whom echocardiographic examination may be appropriate.

Tuberculous perforations of the small intestine

The hospital records of 58 patients operated on for tuberculous perforations of the small intestines at our hospital between 1987 and 1996 were reviewed. Clinical features were non-specific in the majority of the patients. Pneumoperitoneum on abdominal radiographs was present in only 28 (48.3%) patients. Forty-five (77.6%) were operated on within 36 hours of perforation. Surgical management consisted of resection and end-to-end anastomosis (n = 45); oval excision of the perforation and transverse anastomosis reinforced with an omental patch (n = 7); ileo-transverse colostomy (n = 5); and peritoneal drainage only (n = 1). There were 17 deaths (29.3%). Adverse prognostic factors were operation beyond 36 hours (p < 0.01), multiple perforations (p < 0.001), and faecal fistula formation (p < 0.01). Mortality was least with early resection and end-to-end anastomosis of the perforated bowel segment. We conclude that a high index of suspicion is essential for early diagnosis and optimal treatment of patients with tuberculous intestinal perforations.

Haemangiopericytoma of the adult male breast

Haemangiopericytoma is an uncommon, usually benign, soft tissue tumour which has been rarely reported to occur in the female breast. Haemangiopericytoma of the adult male breast has been reported only once before. We report another such case.

Post-infarction ischaemic mitral regurgitation: what determines the outcome

Ischaemic mitral regurgitation is an important determinant of survival in patients with coronary artery disease. A retrospective analysis was performed to evaluate the overall outcome and its determinants in patients with ischaemic mitral regurgitation. Over a period of 10 years, 72 patients underwent operations for mitral regurgitation of ischaemic origin. Age ranged from 37 to 68 years (mean 54.6 +/- 10.4 years), and 62 (86.1%) were male. Thirteen (18%) patients had acute and 59 (82%) had chronic ischaemic mitral regurgitation. Twenty-one patients were in New York Heart Association class II, 32 in class III and 19 in class IV. Moderate to severe left ventricular dysfunction was present in 42 patients. Valve prolapse was present in 35 (48.6%) patients and restricted leaflet motion secondary to myocardial dysfunction was present in 37 (51.4%) patients. All the patients were operated using standard cardiopulmonary bypass technique. Mitral valve was replaced in 33 patients and repaired in 39. Repair included a combination of techniques: chordal transposition (n = 2), chordal shortening (n = 18), leaflet resection (n = 2), posterior collar annuloplasty (n = 35) and annuloplasty with flexible Duran's ring (n = 3). Operative mortality was 18.1 percent (13/72). Low cardiac output was the cause of death in the majority (n = 10). Acute presentation and presence of restricted leaflet motion were the significant predictors of early mortality. Follow-up ranged from 3 to 84 months (mean 41.6 +/- 10.2 months). Late mortality was 46.2 percent. Actuarial survival in operative survivors at five years was 44.4 +/- 8.8 percent. To conclude, ischaemic mitral regurgitation carries a poor early and late outcome, with left ventricular dysfunction and presence of restricted leaflet motion being important contributors to it. In addition, acute presentation also reflects greater early mortality.

Assessment of the stability of N-terminal pro-brain natriuretic peptide in vitro: implications for assessment of left ventricular dysfunction

Plasma concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) are raised in patients with left ventricular dysfunction. Measurement of this peptide has a potential diagnostic role in the identification and assessment of patients with heart failure. The stability of this peptide over time periods and conditions pertaining to routine clinical practice has not been reported previously. Blood samples were obtained from 15 subjects. One aliquot was processed immediately, and the remaining portions of the blood samples were stored for 24 h or 48 h at room temperature or on ice prior to processing. Plasma concentrations of NT-proBNP were measured with a novel immunoluminometric assay developed within our laboratory. Mean plasma concentrations of NT-proBNP were not significantly different whether blood samples were centrifuged immediately and stored at -70 degrees C or kept at room temperature or on ice for 24 h or 48 h. The mean percentage differences from baseline (reference standard) were +5.2% (95% confidence interval +18.2 to -7.8%) and +0.8% (+15.2 to -13.7%) after storage for 24 h at room temperature or on ice respectively, and +8.9% (+24.2 to -6. 5%) and +3.2% (+15.1 to -0.9%) for storage for 48 h at room temperature or on ice respectively. Pearson correlation coefficients for baseline NT-proBNP concentrations compared with levels at 48 h at room temperature or on ice were r=0.89 and r=0.83 respectively (both P<0.0001). Thus NT-proBNP extracted from plasma samples treated with EDTA and aprotinin is stable under conditions relevant to clinical practice.