Neuro-endoscopic surgery--experience and outcome analysis of 102 consecutive procedures in a busy neurosurgical centre of India

BACKGROUND

Neuro-endoscopic surgery is finding increasing application for various clinical conditions. We present our experience of 100 cases of diverse intracranial lesions, including infections, managed by neuro-endoscopy in a busy neurosurgical department in the developing world.

MATERIAL AND METHODS

One hundred patients treated from March 1996 to February 2002 formed the study group. Management of hydrocephalous by Endoscopic third ventriculostomy (ETV) was the aim in 75 patients with or without diagnostic biopsy. Excision or resection was attempted in 25 patients with juxtaventricular or intraventricular lesions. Endoscopic procedures included total tumour resection, partial resection, biopsy, stent placement, Monroplasty, septostomy and third ventriculostomy. Outcomes of endoscopic surgery were evaluated with respect to clinical and/or radiological improvement, complications and need for additional therapy.

FINDINGS

Endoscopy was the only surgical treatment in 59 patients. Intermittent lumbar drainage for cerebrospinal fluid leak, shunt, microsurgery and/or repeat endoscopic surgery were additional treatments needed in 39 patients, who subsequently had increased hospital stay, postoperative morbidity and a higher cost of treatment. Peroperative bleeding due to distorted anatomy and obscured vision in 2 patients with post-infective loculated hydrocephalus (LH) resulted in two fatalities (2%) in the early post-operative period.

INTERPRETATION

Neuro-endoscopic surgery cuts down operative time and hospital stay, reduces cost and results in a faster turnover of the patients. It is a versatile and useful tool for a busy neurosurgical department.

Effectiveness and safety of dolutegravir two-drug regimens in virologically suppressed people living with HIV: a systematic literature review and meta-analysis of real-world evidence

Objectives

Dolutegravir (DTG) is widely recommended within three‐drug regimens. However, similar efficacy and tolerability have also been achieved with DTG within two‐drug regimens in clinical trials. This study evaluated the real‐world effectiveness and discontinuations in people living with HIV‐1 (PLHIV) switching to DTG with lamivudine (3TC) or rilpivirine (RPV).

Methods

This was a one‐arm meta‐analysis utilizing data from a systematic literature review. Data from real‐world evidence studies of DTG + RPV and DTG + 3TC were extracted, pooled and analysed. The primary outcome was the proportion of patients with viral failure (VF; ≥ 50 copies/mL in two consecutive measurements and/or ≥ 1000 copies/mL in a single measurement) at week 48 (W48) and week 96 (W96). Other outcomes included virological suppression (VS; < 50 copies/mL) and discontinuations (W48 and W96). Estimates were calculated for VF, VS as per snapshot (VSS) and on treatment analysis (VSOT), and discontinuations.

Results

Pooled mean estimates of VF for DTG + 3TC and DTG + RPV were 0.8% [95% confidence interval (CI): 0.4–1.3] and 0.6% (95% CI: 0.0–1.6), respectively, at W48. VSS rate at W48 was 85.0% (95% CI: 82.3–87.5) for DTG + 3TC regimen and 92.4% (95% CI: 85.0–97.7) in the DTG + RPV regimen. The DTG + 3TC and DTG + RPV regimens led to discontinuations in 13.6% (95% CI: 11.1–16.2) and 7.2% (95% CI: 2.1–14.4) of patients, respectively, at W48. Similar results were observed at W96.

Conclusions

Treatment with DTG + 3TC or DTG + RPV in clinical practice provides a low rate of VF and a high rate of VS when initiated in virologically suppressed PLHIV with diverse backgrounds.

Inability of laser and rotary instrumentation to eliminate root canal infection

BACKGROUND

The authors evaluated the antibacterial effectiveness of laser instrumentation and rotary instrumentation of anterior, single-rooted teeth infected with Enterococcus faecalis.

METHODS

The authors divided 35 infected samples into five groups: Group A: inoculation, laser, 17 percent ethylene-diamine-tetra-acetate (EDTA), 2.5 percent sodium hypochlorite (NaOCl) (n=10); Group B: inoculation, laser, 17 percent EDTA, sterile saline (n = 10); Group C: inoculation, rotary, 17 percent EDTA, 2.5 percent NaOCl (n=10); Group D: inoculation, no instrumentation (positive control) (n=5); Group E: no inoculation, no instrumentation (negative control) (n=5). They sampled and incubated dentin shavings from each canal for bacterial growth.

RESULTS

In Group A, eight tubes were positive for bacterial growth. In Group B, 10 tubes were positive for bacterial growth. In Group C, six tube were positive for bacterial growth. In Group D, all of the tubes were positive for bacterial growth. In Group E, no tubes showed bacterial growth. The Fisher exact test showed no significant differences among groups A, E and C.

CONCLUSION

Neither the laser nor the rotary instrumentation was able to eliminate endodontic infection.

CLINICAL IMPLICATIONS

Although lasers have been presented as high-tech tools for disinfecting root canals, the laser was ineffective in this study.

Variation in salinity tolerance and shoot sodium accumulation in Arabidopsis ecotypes linked to differences in the natural expression levels of transporters involved in sodium transport

Salinity tolerance can be attributed to three different mechanisms: Na+ exclusion from the shoot, Na+ tissue tolerance and osmotic tolerance. Although several key ion channels and transporters involved in these processes are known, the variation in expression profiles and the effects of these proteins on Na+ transport in different accessions of the same species are unknown. Here, expression profiles of the genes AtHKT1;1, AtSOS1, AtNHX1 and AtAVP1 are determined in four ecotypes of Arabidopsis thaliana. Not only are these genes differentially regulated between ecotypes, the expression levels of the genes can be linked to the concentration of Na+ in the plant. An inverse relationship was found between AtSOS1 expression in the root and total plant Na+ accumulation, supporting a role for AtSOS1 in Na+ efflux from the plant. Similarly, ecotypes with high expression levels of AtHKT1;1 in the root had lower shoot Na+ concentrations, due to the hypothesized role of AtHKT1;1 in retrieval of Na+ from the transpiration stream. The inverse relationship between shoot Na+ concentration and salinity tolerance typical of most cereal crop plants was not demonstrated, but a positive relationship was found between salt tolerance and levels of AtAVP1 expression, which may be related to tissue tolerance.

Comparative attitude and plans of the medical students and young Nepalese doctors

INTRODUCTION

Many doctors are leaving Nepal to work abroad. To understand this problem better, we decided to study the attitude and plans of young doctors and medical students.

MATERIALS AND METHODS

This cross-sectional study was conducted at Kathmandu Medical College involving 65 first year medical students, 100 interns and 100 house officers. The data collected was entered in Microsoft excel and analysed by SPSS (Statistical Package for Social Sciences) programme. Chi-square test was used to compare two proportions. Significance level was set at 5%.

RESULTS

Only 2% house officers said that their job prospects were excellent as compared to 22.4% of students, whereas 20% house officers as compared to 9% students thought job prospects in Nepal were poor (p= 0.003). Eighty two percent of students thought that a doctor's service to his country was very important as compared to 51% of interns (p= 0.001) and 58% of house officers. Forty percent of students, 58% of interns and 48% of house officers (no statistical significance between the three groups) planned to migrate to a developed country after graduation. Eighty eight percent of students, 89% interns and 74% of house officers (no statistical significant differences between the three groups) were of the opinion that improving career opportunities or working environment of the doctor could make the profession more attractive.

CONCLUSION

Although majority of students, interns and house officers were of the opinion that a doctor's service to his community/country was very important, almost half of them still planned to migrate to a developed country after graduation. Improving the chances of professional advancement and professional working environment can make the profession more attractive, and therefore, may decrease this tendency for brain drain from our country.

Congenital supraglottic cyst: a rare cause of stridor

Congenital laryngeal cysts are very rare and if mismanaged, lead to a high incidence of morbidity and mortality. The case may present as severe stridor and emergent management can obviate a tracheostomy, achieving cure in the process. We report here a case of supraglottic cyst, which was completely occluding the airway and was managed in the emergency setting.

Bifunctionally engineered polyethylenimines as efficient DNA carriers and antibacterials against resistant pathogens

In this study, we have designed and developed two series of bifunctional conjugates by tethering polyethylenimine with streptomycin. By varying the amount of streptomycin, conjugates, polyethylenimine-streptomycin, have been synthesized and characterized spectroscopically. Gel electrophoresis assay revealed a slight decrease in the cationic charge density on the conjugates as these retarded the mobility of pDNA at higher w/w ratios. Further, transfection studies showed that both the series of conjugates transfected the mammalian cells efficiently with low-molecular weight polyethylenimine-streptomycin conjugates were more competent (∼9-fold enhancement with respect to native bPEI) exhibiting high cell viability too. Besides, both the series of conjugates displayed excellent antibacterial activity on pathogenic bacteria, even better than native streptomycin on resistant strains. Altogether, these results ensure the promising potential of the projected bifunctional conjugates as safe and efficient gene delivery vectors as well as antibacterials for future biomedical applications.

Gender differences in pulmonary arterial reactivity to dilatory agonists in pulmonary hypertension

OBJECTIVES

To determine whether impaired reactivity to dilatory agonists could contribute to pulmonary hypertension, and whether there are gender differences in pulmonary vasodilator reactivity.

METHODS

Pulmonary arterial rings from monocrotaline (MCT)-induced pulmonary hypertensive and control rats were isolated. At the peaks of submaximal contractions to norepinephrine (NE) or endothelin (ET-1), rings were exposed to 5 x 10(-6) M acetylcholine (ACh) or 9 x 10(-9) M adrenomedullin (ADM) or 1.3 x 10(-8) M calcitonin gene-related peptide (CGRP).

RESULTS

Relaxation to ACh, ADM, and CGRP was endothelium-dependent. Hypertensive pulmonary arterial rings relaxed less to ACh and CGRP than controls in both genders. Female pulmonary hypertensive muscle was more rather than less reactive to ADM compared with controls. ADM-induced relaxation of NE contractions was 2.4 times greater in female compared with male control rings and 5.5 times greater in female compared with male hypertensive preparations. Gender differences in relaxation responses were similar for CGRP. MCT-treated female arterial rings relaxed more than did MCT-treated male arterial muscle in response to ACh. No difference in ACh relaxation was found between genders for controls.

CONCLUSIONS

Pulmonary arterial relaxation to endothelium-dependent vasodilators is impaired in MCT-induced pulmonary hypertension with the exception of ADM in females. Vasodilators may be more effective in reducing pulmonary hypertension in females than in males.

Epidemiology of meningococcal carrier state amongst recruits of a military training centre

An epidemiological study was carried out to determine meningococcal carrier state amongst recruits of a military training centre. 360 recruits with divergent socioeconomic, ethnic backgrounds were studied. Epidemiological factors such as age, religion, educational status, housing conditions, family structure were considered. The overall carrier rate was 11.94%. Carrier rate was higher amongst recruits from poor background and joint families. No association was found between carrier state and smoking as well as those suffering from upper respiratory tract infection. Carrier rate was aslo studied in relation to age, marital status, educational back ground and region.

Numerical simulations of NMR relaxation in chalk using local Robin boundary conditions

The interpretation of nuclear magnetic resonance (NMR) data is of interest in a number of fields. In Ögren (2014) local boundary conditions for random walk simulations of NMR relaxation in digital domains were presented. Here, we have applied those boundary conditions to large, three-dimensional (3D) porous media samples. We compared the random walk results with known solutions and then applied them to highly structured 3D domains, from images derived using synchrotron radiation CT scanning of North Sea chalk samples. As expected, there were systematic errors caused by digitalization of the pore surfaces so we quantified those errors, and by using linear local boundary conditions, we were able to significantly improve the output. We also present a technique for treating numerical data prior to input into the ESPRIT algorithm for retrieving Laplace components of time series from NMR data (commonly called T-inversion).

Differentiation of tuberculous from pyogenic brain abscesses with in vivo proton MR spectroscopy and magnetization transfer MR imaging

BACKGROUND AND PURPOSE

MR imaging features are nonspecific with respect to the causative organism for patients with brain abscesses. On the basis of the hypothesis that the biochemical environment depends on the infecting organism and might be different in tuberculous compared with pyogenic brain abscesses, this study attempted to determine whether pyogenic brain abscesses can be differentiated from tuberculous brain abscesses by use of magnetization transfer (MT) MR imaging and in vivo proton MR spectroscopy.

METHODS

Twenty-seven patients with a total of 33 pyogenic brain abscesses and three patients with a total of 12 tuberculous abscesses were evaluated with in vivo MR spectroscopy and MT MR imaging. The diagnosis in all cases was based on the culture of the causative organisms and histopathology whenever done as a part of clinical management.

RESULTS

All 27 patients with pyogenic brain abscesses had lipid and lactate levels of 1.3 ppm and amino acid levels of 0.9 ppm with or without the presence of succinate, acetate, alanine, and glycine, while the three patients with tuberculous abscesses showed only such lipid and lactate levels. The MT ratio from the wall of the pyogenic abscesses was significantly higher (P <.001) than that from the tuberculous abscess wall.

CONCLUSION

It might be possible to differentiate tuberculous abscesses from pyogenic abscesses by using MT MR imaging and in vivo MR spectroscopy, which could be of value in influencing the management of such cases.