Phytochemistry and biological activity of Erigeron annuus (L.) Pers

Erigeron annuus L. is a flowering herb of North America, Europe, Asia and Russia. This plant is used as folk medicine in China for the cure of indigestion, enteritis, epidemic hepatitis, haematuria and diabetes. Phytochemical studies showed the presence of 170 bioactive compounds like coumarins, flavonoids, terpenoids, polyacetylenic compounds; γ-pyrone derivatives, sterols and various caffeoylquinic acids derived from the essential oil and organic extracts from its various parts such as aerial parts, roots, leaves, stems and flowers. The pharmacological studies demonstrated various extracts and the compounds of E. annuus to exhibit anti-fungal, anti-atherosclerosis, anti-inflammatory, antidiabetic, phytotoxic, cytoprotective, antiobesity and antioxidant activities. This article covers a critical compendious on geographical distribution, botanical description, phytochemistry, ethnomedicinal uses and pharmacological activities of E. annuus. However, further in-depth studies are needed to determine the medical uses of E. annuus and its chemical constituents, pharmacological activities and clinical applications.

The role of dexmedetomidine in post cranioplasty refractory status epilepticus

Cranioplasty, specifically a repair of the skull defect resulting from a previous decompressive craniectomy, is a relatively simple procedure associated with a minimal rate of complications. Even though seizures are seen in up to 30% of the patients postoperatively, status epilepticus is not commonly described. Cerebral oedema, ischaemia and neuro-inflammation have been reported as putative causes of seizures in this population. Here, we report a case of refractory status epilepticus unresponsive to standard anti-epileptic and anaesthetic agents. The use of dexmedetomidine helped terminate the episode and led to a favourable outcome. Most of the standard anti-epileptic and anaesthetic agents act through potentiation of GABAergic transmission or sodium channel blockade and postsynaptic adrenoceptor activation by dexmedetomidine may help potentiate their effect. Further studies are needed to investigate its anticonvulsant effect on post-traumatic brain injury and elaborate on optimal dosage.

Essential oil and nanocarrier-based formulations approaches for vaginal candidiasis

An exclusive site for local drug delivery is the vagina, especially for vaginal infections. The fungus Candida albicans causes vaginal infection known as vulvovaginal candidiasis, a highly prevalent and recurrent gynaecological disease among women. Vaginal candidiasis affects over 75% of women at a certain point in their life and has a recurrence rate of 40-50%. Medicinal plants provide some very effective phytoconstituents which when delivered as nanosystems have enhanced therapeutic action and efficacy by alteration in their characteristics. Antifungal drugs are used to treat these conditions, alternative medicine is required for prophylaxis and improved prognosis. The current review focuses on the research carried out on various nanocarrier-based approaches and essential oil-based formulations for vaginal candidiasis.

Ocular trauma in counter insurgency and proxy war environment: Epidemiological study, 1992-2004

Background

To analyze the epidemiology of hospitalized ocular injuries occurring in counter insurgency and proxy war environment in a forward area of northern India over a period of 13 years.

Methods

Retrospective observational study of medical records was performed of 458 patients with ocular injuries primarily treated at zonal referral hospital of Indian Army between January 1992 and December 2004.

Results

A total of 559 eyes with ocular injuries were studied. The average age of the victims was 30 years. In 77% cases, injuries were sustained by army personnel and remaining by paramilitary forces. Of all cases, 86.5% cases were due to combat-related (militant action), of which 93.9% cases were caused by splinters from munitions. Among the eyes injured due to militant action, 60.36% were open globe injuries, 31.19% were closed globe injuries and 8.45% were isolated adnexal injuries. Among the eyes injured, 76.33% of the eyes with open globe injuries owing to militant action had perforating injuries, whereas in closed globe injuries, 47.74% eyes had corneal foreign body. Among eyes with open globe injuries, Corneo-scleral, scleral and corneal lacerations were seen in 45%, 28% and 27% eyes respectively. 15.75% of eyes with ocular injuries underwent eviscerations.

Conclusion

The study reveals that splinter eye injuries from munitions were the most common cause of ocular morbidity in counter insurgency and proxy war. Implementation of use of protective glasses by the personnel deployed in such hostile environment and strict compliance of preventive measures would be effective in saving eyes and also medical and economic resources.

Multivariate analysis of adaptive response to ferulic acid and p-coumaric acid after physiological stresses in Cronobacter sakazakii

AIM

The present study demonstrated the antimicrobial activity of ferulic acid and p-coumaric acid against unstressed and stressed (cold stressed, starved and desiccated) Cronobacter sakazakii in laboratory media (37°C) and reconstituted powdered infant formulation (PIF) with mild heat treatment (50°C).

METHODS AND RESULTS

Five phenolics, namely, quercetin, rutin, caffeic acid, ferulic acid and p-coumaric acid, were tested for antimicrobial activities against five strains of C. sakazakii either unstressed or stressed. Strain specific higher resistance to ferulic acid and p-coumaric acid was observed after stress adaptation in laboratory media. The effect of cross protection was validated using reconstituted PIF as delivery vehicle of selected compounds. Both p-coumaric acid and ferulic acid showed inhibition of C. sakazakii in a dose and time dependent manner as revealed by their viable cell counts. Principal component analysis revealed that the desiccated cells were more sensitive to phenolics in reconstituted PIF.

CONCLUSIONS

Only ferulic acid and p-coumaric acid showed marked antibacterial activity with minimum inhibitory concentration in the range of 2·5-5 mg ml^-1 for unstressed C. sakazakii cells in tryptone soy broth. The maximum inhibition was achieved with 20 mg ml^-1 of both the tested polyphenols in reconstituted PIF. Cold stress and starvation stress did not impart any protection nor increased the susceptibility of C. sakazakii, whereas desiccation resulted in increased susceptibility to phenolic compounds.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results obtained in this study helps in understanding the effect of environmental stresses during processing on susceptibility of C. sakazakii to natural antimicrobial agents. Future transcriptomic studies and functional genetic studies are warranted to understand the strain specific stress responses for the development of better control methods possibly by using these natural antagonists.

Activation of the receptor tyrosine kinase RET improves long-term hematopoietic stem cell outgrowth and potency

Expansion of human hematopoietic stem cells (HSCs) is a rapidly advancing field showing great promise for clinical applications. Recent evidence has implicated the nervous system and glial family ligands (GFLs) as potential drivers of hematopoietic survival and self-renewal in the bone marrow niche; how to apply this process to HSC maintenance and expansion has yet to be explored. We show a role for the GFL receptor, RET, at the cell surface of HSCs in mediating sustained cellular growth, resistance to stress, and improved cell survival throughout in vitro expansion. HSCs treated with the key RET ligand/coreceptor complex, glial-derived neurotrophic factor and its coreceptor, exhibit improved progenitor function at primary transplantation and improved long-term HSC function at secondary transplantation. Finally, we show that RET drives a multifaceted intracellular signaling pathway, including key signaling intermediates protein kinase B, extracellular signal-regulated kinase 1/2, NF-κB, and p53, responsible for a wide range of cellular and genetic responses that improve cell growth and survival under culture conditions.

Measurement of neutron induced 86Sr(n, 2n)85Sr reaction cross sections at different neutron energies

The cross-sections for ⁸⁶Sr (n, 2n)⁸⁵Sr reaction are measured at neutron energies 19.44 ± 1.02 MeV and 16.81 ± 0.85 MeV wherein there is scarcity of data. The standard neutron activation analysis technique and offline gamma ray spectroscopy have been employed for measurement and analysis of the data. The results are compared with experimental data available in EXFOR database, JEFF-3.3, JENDL-4.0, TENDL-2017 and ENDF/B-VIII.0 evaluated data. The theoretical prediction was incorporated using nuclear modular codes TALYS 1.8 and EMPIRE 3.2.2. A detailed comparative study of experimental results with the theoretical models and various major evaluations has been presented.

Survival and prognostic factors for glioblastoma multiforme: Retrospective single-institutional study

INTRODUCTION

Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor in adults. The standard management has been maximum surgical resection followed by adjuvant radiotherapy with concurrent chemotherapy followed by adjuvant chemotherapy. Although the survival rate of patients with GBM has improved with recent advancements in treatment, the prognosis remains generally poor. The median survival rates are in the range of 9-12 months and 2-year survival rates are in the range of 8%-12%.

MATERIALS AND METHODS

A single-institution retrospective review of 61 patients of GBM from 2012 to 2014. Data regarding patient factors, disease factors, and treatment factors were collected and survival has been calculated.

RESULTS

A total of 61 patients with GBM were analyzed. GBM is commonly seen in sixth decade of life. Male to female ratio is 2.6:1. The right side of the brain is commonly involved with right frontal lobe being the most common site. The median follow-up was 4.6 months. The median survival of our patients was 8 months. The 1-year and 2-year survival rates were 20% and 3.27%, respectively.

CONCLUSIONS

The overall survival and prognosis in patients with GBM remains poor despite of constant research and studies. Concurrent chemoradiotherapy followed by adjuvant chemotherapy with temozolomide should be used after maximal resection to improve the survival.

Successful Renal Transplantation Across HLA Barrier: Report from India

Organ donors are sometimes found “unsuitable” due to the presence of donor-specific anti-HLA antibodies in the recipient. In recent years, improved desensitization protocols have successfully helped to overcome HLA incompatibility hurdle. We present three cases where optimum desensitization was achieved in patients with the donor-specific anti-HLA antibody (DSA) leading to successful renal transplantation. All patient–donor pair underwent HLA typing, complement dependent cytotoxicity crossmatch (CDC-XM), flow cytometry XM (FC-XM), and panel reactive antibody. If any of the three tests was positive, single antigen bead assay was performed to determine the specificity of the anti-HLA antibody (s). Patients with DSA were offered organ-swap or anti-HLA antibody desensitization followed by transplantation. Desensitization protocol consisted of single dose rituximab and cascade plasmapheresis (CP) along with standard triple immunosuppression. The target DSA mean fluorescence index (MFI) was <500, along with negative CDC-XM and FC-XM for both T- and B-cells. Three patients with anti-HLA DSA, who did not find a suitable match in organ swap program, consented to anti-HLA antibody desensitization, followed by transplantation. Mean pre-desensitization antibody MFI was 1740 (1422–2280). Mean number of CP required to achieve the target MFI was 2.3 (2–3). All the three patients are on regular follow-up and have normal renal function test at a mean follow-up of 8 months. This report underlines successful application of desensitization protocol leading to successful HLA-antibody incompatible renal transplants and their continued normal renal functions.

The Learning Curve of Pure Retroperitoneoscopic Donor Nephrectomy

BACKGROUND

Retroperitoneoscopic donor nephrectomy (RDN) is a well-established modality for the procurement of kidneys for renal transplantation. However the learning curve of pure RDN is not yet defined. Defining the learning curve will help in proper mentorship of the new donor surgeons besides providing safety to the donors.

OBJECTIVE

To define the learning curve of pure RDN.

METHODS

We analyzed the prospectively collected data of 102 voluntary kidney donors who underwent RDN by a single surgeon between August 2012 and April 2015 at our center. The donors were classified into group A (1-34), group B (35-68), and group C (69-102) according to the chronological order of their surgery. Left RDN was performed in 28 (82%), 25 (74%), and 28 (82%) donors of group A, B, and C, respectively. Right RDN was performed in 6 (18%), 9 (26%), and 6 (18%) donors of group A, B, and C, respectively. The clinical data were analyzed for each group.

RESULTS

Statistically significant difference was observed for the mean operative time (p<0.01) and warm ischemia time (p<0.04). The operative time remained around 200 minutes after the initial 35 cases.

CONCLUSION

The learning curve of pure RDN was 35 cases, although the mastery requires more number of cases to be performed.

Supraclavicular brachial plexus block using ropivacaine alone or combined with dexmedetomidine for upper limb surgery: A prospective, randomized, double-blinded, comparative study

BACKGROUND

Dexmedetomidine is a new α-2 receptor agonist with analgesic and sedative properties. We used dexmedetomidine along with ropivacaine for supraclavicular brachial plexus block.

METHODS

Eighty ASA grade I-II patients, 18-60 years old, scheduled for elective upper limb orthopaedic surgery under supraclavicular brachial plexus block, were included in this prospective study. The patients were randomly assigned to group R (ropivacaine alone) and group RD (ropivacaine and dexmedetomidine) (40 patients in each group). Group R received ropivacaine 0.50% (30 cc)+placebo and group RD received ropivacaine 0.50% (30 cc)+dexmedetomidine 1 μg/kg. Primary outcome measure was duration of analgesia. Secondary measures were onset and duration of sensory blockade, pain scores, onset and duration of motor blockade, and evidence of any adverse drug reactions.

RESULTS

There was no significant difference hemodynamic parameter during intra-operative period. Group RD showed a statistically significant shorter time to onset of sensory blockade (10.75±2.71 vs. 16.75±2.96 min, P=.003), longer sensory block duration (379.40±55.09 vs. 211.60±47.88 min, P=.002), shorter onset time to motor blockade (14.35±2.58 vs. 20.25±4.13 min, P=.003), longer motor block duration (312.0±49.91 vs. 184.7±36.76 min, P=.002), longer duration of postoperative analgesia (413.73±89.92 vs. 197.35±28.67 min, P=.002). Three patients in the group RD developed somnolence. (P=.04).

CONCLUSION

Dexmedetomidine along with ropivacaine decreases the onset of motor and sensory block and increases the duration of sensory and motor block in supraclavicular brachial plexus block.

Adequacy of twice weekly hemodialysis in end stage renal disease patients at a tertiary care dialysis centre

Hemodialysis has improved the morbidity and mortality associated with end stage renal disease. In India, hemodialysis prescription is empiric, which leads to complications related to under-dialysis. Hence, adequacy of hemodialysis in Indian setting was analyzed in this study. A total of 50 patients on twice per week hemodialysis were assessed for 1 month. The number of sessions meeting standards laid out by Kidney Diseases Outcome Quality Initiatives (KDOQI) guidelines were calculated. They were divided into two groups: one in whom dialysis was monitored and session length enhanced to meet the minimum standard Kt/V of 2 and second control group; where Kt/V was not monitored. Hemoglobin (Hb) levels, albumin levels, mean arterial pressure and World Health Organization (WHO) quality of life (QoL) score were compared in the two groups after 6 months. Only 28% of hemodialysis sessions were adequate as per KDOQI guidelines. There was significant improvement in Hb levels (1.47 vs. 0.15 g/dl), mean arterial pressure levels (15.2 vs. 3.16 mm Hg), serum albumin levels (0.82 vs. 0.11 g/dl) and WHO QoL score (17.2 vs. 2.24) in study group as compared to control group. Standard Kt/V can be used as an important tool to modify twice weekly dialysis sessions to provide better QoL to the patients. However, studies with larger sample size are required to conclusively prove our results.

A vapor phase adsorptive desulfurization process for producing ultra low sulphur diesel using NiY zeolite as a regenerable adsorbent

A NiY zeolite based vapor phase adsorptive desulfurization process has been described which can bring down sulphur concentration of a commercial BS IV grade (Euro IV equivalent) diesel from 50 ppm to a <5 ppm level.

Cytochrome P450-encoding genes from the Heliconius genome as candidates for cyanogenesis

Cytochrome P450s are important both in the metabolism of xenobiotics and the production of compounds such as cyanogenic glucosides, which insects use in their defence. In the present study, we use transcriptomic and genomic information to isolate and name P450-encoding genes from the butterfly Heliconius melpomene. We classify each of the putative genes into its appropriate superfamily and compare the distribution of P450s across sequenced insects. We also identify homologues of two P450s known to be involved in cyanogenesis in the six-spot Burnet moth, Zygaena filipendulae. Classification of Heliconius P450s should be an important step in the dissection of their role in the exploitation of their host plant, the passion vine Passiflora.

Variable functions of bcl-2 in mediating bioreactor stress- induced apoptosis in hybridoma cells

It has been demonstrated that the cell lines used for production of biopharmaceuticals are highly susceptible to apoptosis, and that over-expression of the bcl-2 oncogene can protect cells from death. Stress associated with the deprivation of nutrients has been shown to be the main cause of apoptosis in culture. We have extended these studies by investigating the mechanism of cell death under conditions of sub-optimal pH, shear stress and hyperosmolarity, and the protective action of bcl-2 over-expression. At pH 6, there was no clear evidence of protection from cell death. However, at pH 8, the viability of the bcl-2 transfected cells was about 20% higher relative to the control cells. Cultivation of control cells in a flat bottomed bioreactor with a magnetic stirrer bar without a pivot ring resulted in exposure of the cells to a high attrition effect. As a result, cell growth was retarded and a high level of cell death by apoptosis was observed. Under the same conditions, the bcl-2 transfected cell line exhibited a nearly five fold increase in viable cell number. This finding indicates that under apoptosis-suppressed conditions, shear stress can stimulate cell growth. Batch cultivation of both control and bcl-2 transfected cells in 350 and 400 mOsm media resulted in suppression of cell growth, athough the effect was most marked in the control cell line. Adaptation of control cells to 400 mOsm proved to be impossible to achieve. However, the bcl-2 transfected cells exhibited resistance to the osmotic stress resulting in long term adaptation to a high salt environment. Specific productivity of bcl-2 transfected cells grown in high osmolarity medium was 100% higher than that produced by non- adapted bcl-2 transfected cells grown in normal osmolarity medium. These results demonstrate that bcl-2 has a beneficial effect on hybridoma cultivation under a wide range of culture stresses.

Laparoscopic kidney transplantation: an initial experience

Laparoscopic donor nephrectomy has the advantages of less pain, early ambulation and shorter hospitalization compared to open donor nephrectomy. Kidney recipient surgery is, however, traditionally performed by open surgery. Our aim was to study feasibility and safety of laparoscopic kidney transplantation (LKT). After permission from Internal Review Board, LKT was performed in four patients. All kidneys were procured from deceased donors. Left kidney was used for LKT and transplanted in left iliac fossa while right kidney was used for standard open kidney transplantation (OKT). All transplantation procedures were performed successfully. Cold ischemia time varied between 4 h and 14 h. For LKT, mean time for anastomosis was 65 (range 62-72) min, mean operative time was 3.97 (range 3.5-5) h, mean blood loss was 131.25 mL (range 45-350) mL. Mean wound length was 7 cm in LKT group and 18.4 cm in OKT group. Delayed graft function was observed in one patient in each group. One patient was lost in OKT group due to posttransplant bacterial meningitis. At 6 months, both groups have comparable value of serum creatinine. In conclusion, LKT is technically feasible and safe. Long term outcome needs to be evaluated in a larger study.

Field intensive care--weaning and extubation

Injury following ballistic trauma is the most prevalent indication for providing organ system support within an ICU in the field. Following damage control surgery, postoperative ventilatory support may be required, but multiple factors may influence the indications for and duration of invasive mechanical ventilation. Ballistic trauma and surgery may trigger the systemic inflammatory response syndrome (SIRS) and are important causative factors in the development of acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). However, their pathophysiological effect on the respiratory system is unpredictable and variable. Invasive mechanical ventilation is associated with numerous complications and the return to spontaneous ventilation has many physiological benefits. Following trauma, shorter periods of ICU sedation-amnesia and a protocol for early weaning and extubation, may minimize complications and have a beneficial effect on their psychological recovery. In the presence of stable respiratory function, appropriate analgesia and favourable operational and transfer criteria, we believe that the prompt restoration of spontaneous ventilation and early tracheal extubation should be a clinical objective for casualties within the field ICU.

Profile of chronic hepatitis B virus in children in India: experience with 116 children

BACKGROUND

Hepatitis B virus (HBV) infection in children is mostly asymptomatic and therefore the disease burden is likely to be under appreciated. There is limited information on the profile of chronic HBV infection in children from the Indian subcontinent.

METHOD

In 116 (male:female 89:27) children, aged <15 years, with persistent HBsAg positivity for more than 6 months, a clinical, biochemical, virological and histological assessment was carried out.

RESULTS

At presentation, 21.6% of children were symptomatic, with icterus in 12%. Features of decompensation such as ascites (7%) and gastrointestinal (GI) bleed (5%) were noted uncommonly. Five (4.3%) children had hepatocellular carcinoma (HCC) at presentation. Elevated alanine aminotransferase (ALT) was observed in 76% of subjects (median 61; range 14-815). A significantly higher proportion of children with hepatitis B early antigen (HbeAg) positive status had higher histological activity index (HAI) (84% vs 16%, P < 0.001) and fibrosis score (80% vs 20%, P = 0.007). A strong positive correlation was noted between aspartate aminotransferase (AST), ALT, HBV-DNA and histological severity of the disease (HAI > or =4, fibrosis > or =2). Median HBV-DNA levels were significantly higher in the HBeAg positive compared to the HBeAg negative group (25.6 vs 0.7 pg/mL, P = 0.004). Seventy-four percent of the mothers had evidence of past or present HBV infection.

CONCLUSIONS

Majority of the children with chronic HBV infection are asymptomatic at presentation. HBeAg positive status reflects histologically more severe disease, and a higher level of HBV-DNA. Almost two-thirds of the children may have acquired their HBV infection perinataly.

Over-expression of TATA binding protein (TBP) and p53 and autoantibodies to these antigens are features of systemic sclerosis, systemic lupus erythematosus and overlap syndromes

The aim of this study was to determine the expression levels of p53 and TATA binding protein (TBP) and the presence of autoantibodies to these antigens in Asian Indian patients with systemic sclerosis (SSc), overlap syndromes (OS) and systemic lupus erythematosus (SLE). Fifty patients with SSc, 20 with OS, including mixed connective tissue diseases (MCTD), 20 with SLE, 10 disease controls (DC) and 25 controls (C) were studied. The over-expression of p53 and TBP antigen was determined quantitatively by sandwich enzyme-linked immunosorbent assay (ELISA), varies between four- and sevenfold higher in patients with SSc, OS and SLE, in comparison to DC and C. The expressed protein antigens were not present as free antigens but as immune-complexes. Autoantibodies to p53 were detected by ELISA in 78% subjects with SSc, 100% with OS and 80% with SLE. Autoantibodies to TBP were observed in 28% patients with SSc, 25% with OS and 15% with SLE. In comparison to healthy controls, the titre of antibodies to p53 was significantly higher in patients with SSc (P = 0.00001) than the patients with OS (P = 0.00279) and SLE (P = 0.00289), whereas the titre of antibodies to TBP was higher in patients with OS (P = 0.00185) than the SLE (P = 0.00673) and the SSc (P = 0.00986) patients. Autoantibodies to p53 and TBP were detected in all these patients and the levels of these two autoantibodies showed weak negative correlation with each other. We propose that the over-expression of these antigens might be due to hyperactive regulatory regions in the p53 and TBP gene.

Haematological investigations on fishes infested with fungal growth

Considerable changes have been observed in the haematological parameters of Labeo rohita, Mystus cavasius, Nandus nandus and Puntius sarana infested with Aphanomyces sp., Saprolegnia parasitica, Achlya prolifera and Dictyuchus monosporus, respectively. Substantial decline have been observed in the number of erythrocytes and lymphocytes. The number of granulocytes and monocytes were noticed significantly increased. The amount of haemoglobin has also been decreased drastically in all the cases.

Phacoemulsification cataract extraction and posterior chamber lens implantation in patients with uveitis

PURPOSE

This study reports outcomes of phacoemulsification cataract extraction and posterior chamber intraocular lens implantation within the capsular bag in patients with uveitis.

METHODS

We retrospectively reviewed the charts of 32 patients (39 eyes) with uveitis who underwent phacoemulsification cataract extraction and posterior chamber intraocular lens implantation by two surgeons at The Cleveland Clinic Foundation from January 1990 to June 1998. Patients with less than 3 months of follow-up were excluded.

RESULTS

Diagnoses of uveitis included idiopathic (15 eyes), sarcoidosis (10 eyes), pars planitis (four eyes), CMV retinitis (two eyes), Fuchs heterochromic iridocyclitis (two eyes), syphilis (two eyes), and one eye each of tuberculosis, Crohn's disease, HLA-B27 associated, and acute retinal necrosis. Average follow-up was 20 months (range, 3 to 63 months). Best-corrected visual acuity improved in 37 eyes (95%). Average improvement was 4 +/- 3 Snellen acuity lines (range, 1 to 10 lines). Thirty-four eyes (87%) attained final visual acuity better than or equal to 20/40. Visual loss occurred in one eye (3%) with CMV retinitis. No improvement in visual acuity was seen in one eye (3%) that developed a retinal pigment epithelial detachment. Posterior capsule opacification occurred in 24 eyes (62%), 12 of which required Nd:YAG capsulotomy (31%). Other postoperative complications included recurrence of uveitis (41%), cystoid macular edema (33%), epiretinal membrane formation (15%), and posterior synechiae (8%).

CONCLUSIONS

Phacoemulsification cataract extraction with posterior chamber intraocular lens implantation is safe in patients with uveitis. The incidences of recurrence of uveitis, cystoid macular edema, epiretinal membrane, and posterior synechiae were lower than those reported previously for extracapsular cataract extraction.

Characterization of the Mycobacterium tuberculosis H37Rv alkyl hydroperoxidase AhpC points to the importance of ionic interactions in oligomerization and activity

An alkyl hydroperoxidase (AhpC) has been found frequently to be overexpressed in isoniazid-resistant strains of Mycobacterium tuberculosis. These strains have an inactivated katG gene encoding a catalase peroxidase, which might render mycobacteria susceptible to the toxic peroxide radicals, thus leading to the concomitant overexpression of the AhpC. Although the overexpressed AhpC in isoniazid-resistant strains of M. tuberculosis may not directly participate in isoniazid action, AhpC might still assist M. tuberculosis in combating oxidative damage in the absence of the catalase. Here we have attempted to characterize the AhpC protein biochemically and report its functional and oligomerization properties. The alkyl hydroperoxidase of M. tuberculosis is unique in many ways compared with its well-characterized homologues from enteric bacteria. We show that AhpC is a decameric protein, composed of five identical dimers held together by ionic interactions. Dimerization of individual subunits takes place through an intersubunit disulphide linkage. The ionic interactions play a significant role in enzymic activity of the AhpC protein. The UV absorption spectrum and three-dimensional model of AhpC suggest that interesting conformational changes may take place during oxidation and reduction of the intersubunit disulphide linkage. In the absence of the partner AhpF subunit in M. tuberculosis, the mycobacterial AhpC might use small-molecule reagents, such as mycothiol, for completing its enzymic cycle.

Real-time intraoperative transesophageal echocardiography--how useful? Experience of 5,016 cases

OBJECTIVE

To evaluate transesophageal echocardiography (TEE) as an intraoperative monitoring modality and to assess its safety, reliability, and overall utility in real-time use during cardiac surgery.

DESIGN

Prospective, observational cohort study performed from January 1993 to June 1997.

SETTING

Operating room of a tertiary care hospital for cardiology and cardiovascular surgery.

PARTICIPANTS

Five thousand and sixteen adult patients with acquired heart disease, who underwent 1,356 valve procedures and 3,660 coronary artery bypass graftings (CABGs).

INTERVENTIONS

All patients were monitored with radial artery and pulmonary artery catheters, along with continuous TEE monitoring with a multiplane transducer.

MEASUREMENTS AND MAIN RESULTS

Prebypass imaging yielded unsuspected findings that either helped or modified the surgical plan in 158 of 1,356 valve procedures (11.65%) and in 993 of 3,660 CABGs (27.13%). There were 3,217 TEE-guided hemodynamic interventions in 944 patients (25.79%) in the CABG group and 629 in 142 patients (10.47%) in the valve group. TEE was the sole guiding factor in initiating therapy in 23.53% of events, whereas it was supportive to other monitoring modalities in 76.46% of events. Postbypass TEE identified the need for graft revision in 29 patients (0.8%), intra-aortic balloon pump (IABP) requirement in 29 patients (0.8%), and inadequate valve repair in 28 patients (2.08%). For the entire series, 38.78% of patients benefited from prebypass and 39.16% from postbypass use of TEE. There were no complications attributable to the use of TEE in the entire series. There was 87% concordance between online interpretation by a trained anesthesiologist and offline analysis by a cardiologist.

CONCLUSION

Intraoperative TEE is useful in formulating the surgical plan, guiding various hemodynamic interventions, and assessing the immediate results of surgery. It is safe and the results are reliable in the hands of trained anesthesiologists.