bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Weather Years and Climatic Parameters on Yield of Maize Varieties under Sub-tropical Condition of Nepal
Authors: Bhusal Tej Narayan , Timsina Jagdish
Published: January 2011

Recent trends of climate change have raised serious concerns about the food production not only in regional levels but locally and globally. The well calibrated and validated Crop Simulation Model (CSM)-Crop Environment Resource Synthesis (CERES)-Maize (v 4.0) model and secondary crop data were used to test sensitivity of this model in subtropical condition of Nepal. The model was sensitive to climatic parameters (temperatures CO2 concentration and solar radiation) and weather years on yields of Rampur Composite, Upahar and Arun-4. The simulated yield for Rampur Composite and Arun-4 were 13.41% and 16.89% higher, respectively in 2006, while it was 0.12% higher for Upahar in 2005 than the yield of maize in 2007. Likewise, decrease in both maximum and minimum temperature by 4°C with respect to either solar radiation (±1MJm-2day-1) and CO2 (+20 ppm) change or not change, maize yield increased by 11.72-49.11% as compared to base scenario while it was decreased by 32.22-2.83% for increase in both maximum and minimum temperature by 4°C along with either change in solar radiation (±1MJm-2day-1) and CO2 (+20 ppm) or remains same. Results revealed that the temperature is more critical for yield potentiality of cultivars than any other climatic parameters. Screening out and adopting of new technology would be required to combat with changing climatic scenarios for attaining the potential yield of maize. CERES Key words: CSM-CERES-maize; simulation; calibration; validation; grain yield DOI: 10.3126/njst.v11i0.4084Nepal Journal of Science and Technology 11 (2010) 17-24
Botanical Control of Late Blight of Potato
Authors: Maharjan BL , Shreshta K , Basnyat S
Published: January 2011

Late blight caused by Phytophthora infestans (Mont.) De Bary is one of the most devastating diseases of potato. Although a large number of synthetic fungicides have been recommended to control this organism, most of them have proved to be pollutive, carcinogenic and the pathogen develops resistance quickly. Botanical control is one of the safe substitutes to be explored to control this phytopathogen. In the present study an attempt has been made to evaluate the antifungal activity of plant extracts against the above pathogen. Crude ethanolic extracts of five different plant materials viz. Brassica nigra, Cinnamomum camphora, Eupatorium adenophorum, Lantana camara and Melia azedarach were screened and tested against the fungal isolate of P. infestans. The antifungal activity of the crude extracts was evaluated by agar well diffusion method and two fold broth dilution method. The moisture content was highest in the twigs of L. camara and lowest in the cake of B. nigra. C. camphora gave the highest yield of 70% while M. azedarach had the lowest yield of (9.75%) of crude extracts. B. nigra was found most effective against P. infestans with both MIC and MFC values at 6.25mg/ml while C. camphora was found least effective. Different types of plant extracts with different concentrations significantly (P<0.05) inhibited the growth of the pathogen. The extracts used in this experiment were found to be suitable for the control of the pathogen. Key words: botanical control; antifungal; MIC; ZOI; MFC DOI: 10.3126/njst.v11i0.4087Nepal Journal of Science and Technology 11 (2010) 37-40
Influence of Seasons and Varieties on Vase Life of Gerbera (Gerbera jamesonii Hook.) Cut Flower
Authors: Acharya Anil Kumar , Baral Dilli Ram , Gautam Durga Mani , Pun Umed Kumar
Published: January 2011

Postharvest studies were carried out in three varieties of (Gerbera jamesonii Hook.) cvs. Primrose, Malibu and Sunway to find out the effect of growing seasons (autumn, winter and spring) on the vase life of cut flowers during September 2009 to March 2010. Laboratory experiments were carried out in controlled room having 18±2°C temperature, 68±2% relative humidity and 100 lux light. The study revealed that the longest vase life was noticed in Sunway, followed by Primrose and Malibu. Regarding the season of production, longest vase life (18.37 days) was found in the flowers harvested in winter, followed by spring (14.8 days) and autumn (9.57 days). The interaction effect of season and variety showed that longest vase life (23.2 days) was found in Sunway harvested in winter whereas the shorter vase lives (5.7 and 7.8 days) were in Malibu and Primrose respectively harvested in autumn. Stalk length (57.88 cm) and floral diameter (10.78 cm) were highest in autumn while diameter of the stalk (0.64 cm) was the highest in spring. Sunway had the highest floral and stalk diameters, while the stalk length was longer in Malibu and Primrose. Total water uptake during the vase life was highest in flowers grown in winter (34.9 ml), followed by spring (34.7 ml) and autumn (26.14 ml). Key words: floral diameter; floriculture; postharvest; vase life; water uptake DOI: 10.3126/njst.v11i0.4088Nepal Journal of Science and Technology 11 (2010) 41-46
Pollen Germination in Different Genotypes of Gladiolus
Authors: Poon Tul Bahadur , Rao TM , Aswath C , Rajasekharan PE , Kumar DP
Published: January 2011

Fresh pollen of 16 promising genotypes of gladiolus was tested for their pollen viability. Modified cellophane method was employed to assess the pollen viability. Pollen germination media consisted of 15% sucrose supplemented with 300 ppm calcium nitrate, 200 ppm magnesium sulphate, 100 ppm potassium nitrate and 100 ppm boric acid. Highly significant variations were observed for percentage of pollen germination, non-germinated pollen and sterile pollen. The highest pollen germination (76.41%) was in genotype Hybrid selection 88-10-22, and did not differ significantly from Gladiolus callianthus (75.41%), Sapna (75.10 %), Hybrid selection 86-32-11, (73.28 %), Kum Kum (69.41%), Poonam (69.22 %), Hybrid selection 87-22-1 (67.87 %), Hybrid selection 87-1-1 (67.61 %), Psittacinus hybrid (64.64%) and Darshan (63.97%). The lowest non- germinated pollen (10.47%) was in genotype Gladiolus callianthus, and insignificantly followed by Hybrid selection 88-10-22 with 18.77 % and Hybrid selection 87-22-1 with 18.95 %. The lowest percentage of sterile pollen was noticed in genotype Sapna (2.82%) followed by Poonam with 4.00 % Hybrid selection 88-10-22 with 4.82% and Hybrid selection 82-11-27 with 5.22%. Key words: Gladiolus; germination; pollen DOI: 10.3126/njst.v11i0.4089Nepal Journal of Science and Technology 11 (2010) 47-50
Comparison of Commercial and Local Varieties of Radish at Different Levels of Manures and Fertilizers
Authors: Chapagain Tika Rak , Piya Sharmila , Dangal Nabin Kumar , Mandal Jawahar Lal , Chaudhary Bhanu Prasad
Published: January 2011

Five commercial (Any sesion, Tikimashi, Mino Early, Forty Days and Chetki) and a local (Bhedetar Local) varieties of radish were tested at the Agricultural Research Station (ARS), Pakhribas, Dhankuta, during the autumn season of 2008 and 2009 for their performance at different levels of manures and fertilizers. Two trials, varietal and fertilizer were conducted in randomized complete block design with four replications. The highest root yield (65.1 t ha-1) was obtained from Mino Early which was at par with Bhedetar Local (62.85t ha-1) in varietal trial. In fertilizer trial, the highest mean root yield of Bhedetar Local was obtained from 100:80:40 N2:P2O5:K2O kg ha-1 + FYM 20 t ha-1 which was at par with 75:50:50 N2:P2O5:K2O kg ha-1 + FYM 20 t ha-1, however, differed statistically with other treatments. The root yield obtained from the exiting farmers practice was statistically at par with 75:50:50 N2:P2O5:K2O kg ha-1. Root yield (t ha-1) was positively and significantly (≥0.01) correlated with root length, plant height, root diameter and number of leaves per plant. Key words: Bhedetar Local; fertilizers; radishDOI: 10.3126/njst.v11i0.4090Nepal Journal of Science and Technology 11 (2010) 51-56
Effect of Climate Change on Rice Production: A Case of Six VDCs in Jumla District
Authors: Sapkota Sudha , Paudel Mina Nath , Thakur Naresh Singh , Nepali Megh Bahadur , Neupane Reshma
Published: January 2011

Rice (Oryza sativa L.) is a staple crop of Nepal and is directly associated with ample water and minimum fluctuation of temperature that could affect on its production. Jumla is the unique place where rice is cultivated in the highest altitude (3000 m) in the world. To find out changes in rice production due to climatic effect, six VDCs of Jumla were chosen for the study. Household survey, participatory rapid appraisal, farmers’ group discussions and desk review were used for collecting data. Rice varieties Chandannath-1 andChandannath-3 were disseminated by the formal seed system with the aim of increasing rice productivity. Despite the replacement of local varieties by improved ones the production trend seems to be stagnant. One of the factors on stagnant of rice production in Jumla is due to the lack of desirable variety with genetic traits of early maturity, less nutrient requirement compared to Jumli Marshi to cope up with the climate congruently supporting to cultural practices regarding the unique rice production systems of Jumla. Key words: climate change; rice production; highest altitude; seed DOI: 10.3126/njst.v11i0.4124Nepal Journal of Science and Technology 11 (2010) 57-62
Evaluation of Wool Production Performance on Different Lines and Strains of Angora Rabbit at Khumaltar, Lalitpur
Authors: Neupane Damodar , Dhaubhadel Tribhubaneshowr , Neopane Shree Ram Prashad
Published: January 2011

Research on wool production performance between different lines and strains of Angora rabbit was started at Swine and Avian Research Program(SARP), Khumaltar, Lalitpur since 1994. The high yielding lines of German (G1) and Chinese Angora were introduced at SARP in 1998 from Chitlang Goat Farm of Department of Livestock Services(DLS) and Lumle Agriculture Research Center. Research on wool production performance of German, Chinese, Russian and British strains of Angora rabbit at Khumaltar, Lalitpur was conducted . Based upon the one year data G1 line of German Angora showed significantly (P ≤ 0.05 ) higher wool production( 949.2 + 101g /rabbit /year) than other lines and strains of Angora rabbit . The average annual wool production in Chinese Angora, G2 line of German Angora, Russian Angora and British Angora were 656.2 g, 511g, 349.5 g and 335 g respectively. Similarly, additional improvement on management for existing lines and strains also showed significant (P ≤ 0.05 increase on wool production performance as compared with the result of previous year(G2 line of German 423.125 g to 511 g and British 305 g to 349 g). Key words: Angora rabbit; F1 generation; wool production. DOI: 10.3126/njst.v11i0.4128Nepal Journal of Science and Technology 11 (2010) 83-86
Effect of Packaging Materials and Modified Atmosphere Packaging on the Shelf-life of Khoa
Authors: Acharya Pushpa Prasad , Agrawal Joyti
Published: January 2011

Preservation of freshly prepared Khoa was carried out at room temperature (25±1°C) and refrigerated temperature (5±1°C) by using different packaging materials such as LDPE, aluminum foil/PVC and three layer laminated (polyester/ met. BOPP/LDPE) in different conditions viz. normal and shrink. All of the packaging materials on both conditions showed no significant difference except normal LDPE on mean sensory score and chemical parameters of Khoa during storage at 5±1°C whereas it showed highly significant difference at 25±1°C among three packaging materials. Three layer laminated sample showed significantly higher sensory quality, high pH, low acidity, peroxide value (PV), free fatty acids (FFA) and lower microbial count than other two packaging materials. Similarly, shrink packaged sample showed better quality in terms of sensory and microbial attributes of Khoa compared to normal packaging. No colonies of yeast and mold, coliform were observed during the storage period. Shrink packaged Khoa in three layer laminated increased storability to 27 days at 25±1°C against three days for unpacked ordinary Khoa. Key words: Khoa preservation; packaging materials DOI: 10.3126/njst.v11i0.4129Nepal Journal of Science and Technology 11 (2010) 87-94
Symbiotic Properties of Rhizobial Isolates of Manang and Kathmandu Districts
Authors: Baral Bikash , Gupta Vimal Narayan
Published: January 2011

Nitrogen is a major limiting factor for primary production in any ecosystem and also the vital component of nucleic acids, proteins, chlorophylls and many other metabolic molecules. Legume-Rhizobium symbiotic system is known to be an efficient converter of ambient nitrogen into its nutrient form that increases soil fertility. The present work involved isolation, characterization and authentication of two rhizobial isolates, KR1 and MR2 obtained by trap method using broad bean (Vicia faba L.) from the field soils of Kathmandu and upper Manang (trans-himalayan region). Their culture characters and symbiotic effectiveness were analysed using standard methods. V. faba was used to study their effectiveness on various parameters such as plant height, roots length, shoot length, nodule number, nodules biomass, plant biomass, content of ureides in xylem sap, as indicative to fixed nitrogen and total nitrogen in nodules, stem and leaves were studied. Viable cell counts at 72h of growth were 17.8x107 for MR2 and 14.1x107 for KR1. The isolates were similar for nodulation, plant biomass and nodule nitrogen (P≥0.05) the MR2 affected vigorous plant growth. However, the isolates showed significant differences (P≤0.05) with plant age on all the parameters studied. The kinetics of inoculation effects on nodulation, plant height, biomass, and total nitrogen were dealt with. Key words: Rhizobium; rhizobial isolates; nodules; translocation DOI: 10.3126/njst.v11i0.4130Nepal Journal of Science and Technology 11 (2010) 95-100
Vegetation Dynamics in Treeline Ecotone of Langtang National Park, Central Nepal
Authors: Gaire NP , Dhakal YR , Lekhak HC , Bhuju DR , Shah SK
Published: January 2011

A study was carried out at the treeline ecotone (3,730m-3,950m asl) of Langtang National Park in central Nepal with an aim to document the impact of climatic warming on ecological chracteristics. Three sampling sites were selected at Chaurikharka and Lauribina, where no serious anthropogenic pressure was noticed. The nearest meteorological station has records of climatic warming in recent years. Six tree species and three shrub species belonging to seven families were enumerated from the study plots. The average basal area for tree species was found to be 20.56 m2 per ha while average tree density was found to be 734 trees per ha with Abies spectabilis as dominant species. The mean DBH (diameter at breast height) of tree species was found to be 15.8 cm (max. 115.5cm). Density of dead trees accounted 2 no. per ha with basal area 0.195m2 per ha. Average sapling and seedling density of tree species per ha was observed to be 1,590 and 831 respectively. The average sapling and seedling density of A. spectabilis was 255 and 350 per ha respectively. Similarly, average shrub density (per ha) for the area was found to be 9,609 no/ha. The stand character showed that there was high level of recruitment of A. spectabilis in the recent years. The presence of sapling and seedling of A. spectabilis at higher altitude showing linear relationship with canopy coverage indicated prospects for a gradual and upward shift of A. spectabilis with increased temperature. Key words: Abies spectabilis; regeneration; climate change; DBH DOI: 10.3126/njst.v11i0.4132Nepal Journal of Science and Technology 11 (2010) 107-114
Floral Phenology and Pollination Ecology of Punica granatum L. in Kathmandu, Nepal
Authors: Adhikari Subodh , Adhikari Mahesh Kumar
Published: January 2011

The phenological and ecological study on Punica granatum L., a cultivated and wild species found in outer Himalayan ranges and warm inner valleys (alt. 700 - 2700m), was carried out during April and May of 2006 and 2007 in Kathmandu Valley. The study covered blooming time, size of flower, its correlation and interaction with the visitors and pollinators. The prime pollinator was Apis cerena along with A. mellifera. Normal range of the length of a full blooming flower (mature flower) was 4.1 to 4.7 cm (in bagged flower) and 3.8 to 4.9 cm (in open flower). The fruiting rate was higher in case of the open flowers than the bagged one. Visitor's/pollinator's flower visit rate (visits/time) was found higher (most effective) in morning with sunny weather (766 times out of 1365). Similarly, the least effective time was dawn and dusk with cloudy and rainy weather (2 times each out of 1365). Key words: floral phenology; visitors/pollinators DOI: 10.3126/njst.v11i0.4133Nepal Journal of Science and Technology 11 (2010) 115-124
Trade and Sustainable Conservation of Swertia chirayita (Roxb. ex Fleming) h. Karst in Nepal
Authors: Phoboo Susanna , Jha Pramod Kumar
Published: January 2011

Swertia chirayita (Roxb. ex Fleming) H. Karst is one of the most important high-value medicinal plants of Nepal prized for its anti-diabetic, antimalarial, hepato-protective and anti-inflammatory properties. It is widely used as an important ingredient in medicinal preparations in Ayurveda, Unnani, Siddha, Tibetan and Chinese traditional medicine. Nepal is one of the main exporters of this important plant and the most significant importers are India and China. The large scale export of this plant has made it vulnerable in Nepal and there is an immediate need for its conservation. Detailed information on the current status of trade of this plant in Nepal is necessary to understand and make assumptions on its current market standing or future predictions of demand. S. chirayita is traded in 61 of the 75 districts of Nepal and constituted about 3% in the total medicinal plant traded in the fiscal year 2008-2009. Due to extensive collection of S. chirayita from the wild, there is a need for exploring alternative conservation options in order to preserve the remaining wild population. Sustainable harvesting and cultivation can help in its conservation. This paper briefly reviews the state of trade and sustainable conservation of this important medicinal plant in Nepal. Key words: Swertia chirayita; trade; cultivation; sustainable use; sustainable harvesting DOI: 10.3126/njst.v11i0.4134Nepal Journal of Science and Technology 11 (2010) 125-132
Biological Activities of Three Different Medicinal Plants from Himalayan Region of Nepal
Authors: Bhattarai Keshab , Shrestha Tirtha Maiya , Bajracharya Ramita , Jain SC , Lamichhane Janardan
Published: January 2011

Crude chloroform/methanol and methanol extracts of leaves and twigs of three medicinal plants collected from different altitudes of Nepal, Rhododendron lepidotum, Hippophae rhamnoids and Cornus capitata were examined for their antibacterial, cytotoxicity and antiproliferative activities. The antimicrobial activity shown by methanol extracts of R. lepidotum and C. capitata against Staphylococcus aureus was comparable with that of streptomycin antibiotic whereas the activity of the extract of H. rhamnoids was very low. Cytoxicity (LC50) values ranged from 46.4 to 111.6 μg/ml with R. lepidotum and 129.4 to 464.1 μg/ml with C. capitata indicating high cytoxic property in the extract of R. lepidotum and medium in C. capitata. Similarly, anti-proliferative activity of R. lepidotum against HeLa cell line was relatively high activity in comparison to C. capitata and H. rhamnoids. Phytochemical screening revealed the presence of flavonoids, tannins, terpenoids, steroids, glycosides and coumarins, which could be responsible for the bioactivities shown by these plants. Key words: antibacterial; antiproliferative; microtitration; HeLa cells DOI: 10.3126/njst.v11i0.4136Nepal Journal of Science and Technology 11 (2010) 139-146
Solid-supported Synthesis of 3, 4-dihydrobenzo [2, 3-d] pyrimidines
Authors: Mishra AD
Published: January 2011

Different 3,4-dihydrobenzo[2,3-d] pyrimidine derivatives were synthesized by the condensation of substituted 1, 3- cyclohexadienes and formamide, using inorganic solid supports under microwaves. Simple and commonly available compounds were used as starting materials in the reactions. The compounds were tested against different fungal and bacterial strains and found considerably effective. Key words: inorganic solid supports; microwave; benzopyrimidines; environmentally benign; antimicrobial DOI: 10.3126/njst.v11i0.4138Nepal Journal of Science and Technology 11 (2010) 153-158
Wind Energy Resource Assessment and Feasibility Study of Wind Farm in Kaligandaki Riverbank of Mustang District
Authors: Ghimire Mukesh , Poudel Ram C
Published: January 2011

This study presents wind energy resource assessment and financial analysis of a 15 MW wind farm in Mustang for utility scale power generation. Hourly meteorological data at Kagbeni and Thini measured at 10 m and 20 m height from 2001 to 2005 have been analyzed and annual average wind speed and power density at 75 m above ground level at Kagbeni 8.05 m/s and 851 W/m2 whereas the same for Thini are 6.99 m/s and 337 W/m2 respectively.WAsP analysis showed that the wind speed and wind power density in the study area (20 × 20 km2) varied from 2.72 m/s to 44.51 m/s and 0.23 kW/m2 to 173.27 kW/m2. Optimized layout of a 15 MW wind farm that comprised of twenty five S52 -600 kW turbines, developed by open Wind software yields annual gross energy 63.58 GWh, and net energy 41.66 GWh with capacity factor of 31.68 %. The economic analysis of the farm suggests that the unit energy cost stands on range NRs 4.57 to NRs 6.10 under different energy availability scenario to meet the project MARR of 16.1%. Based on the results, it is apparent that the wind resources at Mustang are suitable for harnessing wind energy especially for the purpose of utility scale electricity generation. Site accessibility is a major challenging factor to establish a wind farm currently. Key words: WAsP; wind energy; wind farm DOI: 10.3126/njst.v11i0.4139Nepal Journal of Science and Technology 11 (2010) 159-166
Status and Distribution Pattern of Barking Deer (Muntiacus muntjak Zimmermann) in Hemja VDC, Kaski
Authors: Pokharel K , Chalise MK
Published: January 2011

Barking deer (Muntiacus muntjak Zimmermann) is a solitary and forest dwelling ruminant. A study was carried out to know status and distribution of barking deers found in the forested mountains of Hemja VDC, Kaski District. The study was done by direct observation method with indirect counting of fecal pellets while walking systematically in total 11 line transects covering 6.64 km in length and a total of 20 quadrates with 20×20m2 - 40×40m2 randomly laid down in three different sites of the study area. A total of 12 individuals (5 adult males, 4 adult females, 2 sub-adult females and 1 infant), 178 pellet groups, 13 latrines and one hunting spot were recorded inside three different blocks of the study area. The results showed clumped and uneven distribution of this deer. It prefers middle range of the mountain (1100-1300m) with dense canopy cover, proper water sources and less human disturbances. Key words: barking deer; distribution patternDOI: 10.3126/njst.v11i0.4149Nepal Journal of Science and Technology 11 (2010) 223-228
Low-back pain as the presenting sign in a patient with a giant, sacral cellular schwannoma: 10-year follow-up
Authors: Alfieri Alex , Campello Mauro , Broger Maximilian , Vitale Mario , Schwarz Andreas
Published: January 2011

Giant sacral tumors present unique challenges to surgeons because there is no established consensus regarding the best treatment options. The authors report on the care of and outcome in a patient presenting with low-back pain only, who underwent preoperative biopsy sampling and subsequent embolization of the feeding vessels of a giant, sacral cellular schwannoma. The main procedure was performed via a combined posterior-anterior approach with complete microsurgical removal of the tumor, without the use of instrumentation, bracing, or adjuvant radio- and chemotherapy. At the 10-year follow-up, no evidence of residual tumor, recurrence, or instability was recognizable. Giant, sacral cellular schwannomas can be aggressively completely removed without any significant morbidity, achieving long-term control of the disease.
Correlation of preoperative depression and somatic perception scales with postoperative disability and quality of life after lumbar discectomy
Authors: Chaichana Kaisorn L. , Mukherjee Debraj , Adogwa Owoicho , Cheng Joseph S. , McGirt Matthew J.
Published: January 2011

Object

Lumbar discectomy is the most common surgical procedure performed in the US for patients experiencing back and leg pain from herniated lumbar discs. However, not all patients will benefit from lumbar discectomy. Patients with certain psychological predispositions may be especially vulnerable to poor clinical outcomes.

The goal of this study was therefore to determine the role that preoperative depression and somatic anxiety have on long-term back and leg pain, disability, and quality of life (QOL) for patients undergoing single-level lumbar discectomy.

Methods

In 67 adults undergoing discectomy for a single-level herniated lumbar disc, the authors determined quantitative measurements of leg and back pain (visual analog scale [VAS]), quality of life (36-Item Short Form Health Survey [SF-36]), and disease-specific disability (Oswestry Disability Index) preoperatively and at 6 weeks, 3, 6, and 12 months after surgery. The degree of preoperative depression and somatization was assessed using the Zung Self-Rating Depression Scale and a modified somatic perception questionnaire (MSPQ). Multivariate regression analyses were performed to assess associations between Zung Scale and MSPQ scores with achievement of a minimum clinical important difference (MCID) in each outcome measure by 12 months postoperatively.

Results

All patients completed 12 months of follow-up. Overall, a significant improvement in VAS leg pain, VAS back pain, Oswestry Disability Index, and SF-36 Physical Component Summary scores was observed by 6 weeks after surgery. Improvements in all outcomes were maintained throughout the 12-month follow-up period. Increasing preoperative depression (measured using the Zung Scale) was associated with a decreased likelihood of achieving an MCID in disability (p = 0.006) and QOL (p = 0.04) but was not associated with VAS leg pain (p = 0.96) or back pain (p = 0.85) by 12 months. Increasing preoperative somatic anxiety (measured using the MSPQ) was associated with decreased likelihood of achieving an MCID in disability (p = 0.002) and QOL (p = 0.03) but was not associated with leg pain (p = 0.64) or back pain (p = 0.77) by 12 months.

Conclusions

The Zung Scale and MSPQ are valuable tools for stratifying risk in patients who may not experience clinically relevant improvement in disability and QOL after discectomy. Efforts to address these confounding and underlying contributors of depression and heightened somatic anxiety may improve overall outcomes after lumbar discectomy.
Biomechanical advantage of the index-level pedicle screw in unstable thoracolumbar junction fractures
Authors: Baaj Ali A. , Reyes Phillip M. , Yaqoobi Ali S. , Uribe Juan S. , Vale Fernando L. , Theodore Nicholas , Sonntag Volker K. H. , Crawford Neil R.
Published: January 2011

Object

Unstable fractures at the thoracolumbar junction often require extended, posterior, segmental pedicular fixation. Some surgeons have reported good clinical outcomes with short-segment constructs if additional pedicle screws are inserted at the fractured level. The goal of this study was to quantify the biomechanical advantage of the index-level screw in a fracture model.

Methods

Six human cadaveric T10–L4 specimens were tested. A 3-column injury at L-1 was simulated, and 4 posterior constructs were tested as follows: one-above-one-below (short construct) with/without index-level screws, and two-above-two-below (long construct) with/without index-level screws. Pure moments were applied quasistatically while 3D motion was measured optoelectronically. The range of motion (ROM) and lax zone across T12–L2 were measured during flexion, extension, left and right lateral bending, and left and right axial rotation.

Results

All constructs significantly reduced the ROM and lax zone in the fractured specimens. With or without index-level screws, the long-segment constructs provided better immobilization than the short-segment constructs during all loading modes. Adding an index-level screw to the short-segment construct significantly improved stability during flexion and lateral bending; there was no significant improvement in stability when an index-level screw was added to the long-segment construct. Overall, bilateral index-level screws decreased the ROM of the 1-level construct by 25% but decreased the ROM of the 2-level construct by only 3%.

Conclusions

In a fracture model, adding index-level pedicle screws to short-segment constructs improves stability, although stability remains less than that provided by long-segment constructs with or without index-level pedicle screws. Therefore, highly unstable fractures likely require extended, long-segment constructs for optimum stability.
Trajectory of the main sensory and motor branches of the lumbar plexus outside the psoas muscle related to the lateral retroperitoneal transpsoas approach
Authors: Dakwar Elias , Vale Fernando L. , Uribe Juan S.
Published: January 2011

Object

The minimally invasive lateral retroperitoneal transpsoas approach is increasingly used to treat various spinal disorders. Accessing the retroperitoneal space and traversing the abdominal wall poses a risk of injury to the major nervous structures and adds significant morbidity to the procedure. Most of the current literature focuses on the anatomy of the lumbar plexus within the substance of the psoas muscle. However, there is sparse knowledge regarding the trajectory of the lumbar plexus nerves that travel along the retroperitoneum and abdominal wall muscles in relation to the lateral approach to the spine. The objective of this study is to define the anatomical trajectories of the major motor and sensory branches of the lumbar plexus that are located outside the psoas muscle.

Methods

Six adult fresh frozen cadaveric specimens were dissected and studied (12 sides). The relationship between the retroperitoneum, abdominal wall muscles, and the lumbar plexus nerves was analyzed in reference to the minimally invasive lateral retroperitoneal approach. Special attention was given to the lumbar plexus nerves that run outside of psoas muscle in the retroperitoneal cavity and within the abdominal muscle wall.

Results

The skin and muscles of the abdominal wall and the retroperitoneal cavity were dissected and analyzed with respect to the major motor and sensory branches of the lumbar plexus. The authors identified 4 nerves at risk during the lateral approach to the spine: subcostal, iliohypogastric, ilioinguinal, and lateral femoral cutaneous nerves. The anatomical trajectory of each of these nerves is described starting from the spinal column until their termination or exit from the pelvic cavity.

Conclusions

There is risk of direct injury to the main motor/sensory nerves that supply the anterior abdominal muscles during the early stages of the lateral retroperitoneal transpsoas approach while obtaining access to the retroperitoneum. There is also a risk of injury to the ilioinguinal, iliohypogastric, and lateral femoral cutaneous nerves in the retroperitoneal space where they travel obliquely during the blunt retroperitoneal dissection. Moreover, there is a latent possibility of lesioning these nerves with the retractor blades against the anterior iliac crest.
Lumbar artery pseudoaneurysm after percutaneous vertebroplasty: a unique vascular complication
Authors: Puri Ajit S. , Colen Rivka R. , Reddy Arra S. , Groff Michael W. , DiNobile Diane , Killoran Timothy , Nikolic Boris , Thomas Ajith J.
Published: January 2011

Complications from percutaneous vertebroplasty (PV) and kyphoplasty are rare and are most commonly related to cement leakage. Pseudoaneurysm of the segmental arteries has not been reported as a complication of PV in the literature. In this article, the authors describe 2 patients who presented with a lumbar pseudoaneurysm after undergoing PV at other institutions. The authors also review the optimal technique to avoid such vascular complications.
Clinicopathological factors related to regrowth of vestibular schwannoma after incomplete resection
Authors: Fukuda Masafumi , Oishi Makoto , Hiraishi Tetsuya , Natsumeda Manabu , Fujii Yukihiko
Published: January 2011

Object

The authors retrospectively analyzed various clinicopathological factors to determine which are related to regrowth during a long-term follow-up period in patients who underwent incomplete vestibular schwannoma (VS) resection.

Methods

This study involved 74 patients (25 men and 49 women) in whom a VS was treated surgically via the lateral suboccipital approach, and who had postoperative follow-up periods exceeding 5 years. The mean follow-up was 104.1 months (range 60–241 months), and the mean patient age at surgery was 48.1 years (range 19–75 years). The tumors ranged in size from 0 mm (localized within the internal auditory canal) to 56 mm (28.3 ± 12.2 mm [mean ± SD]).

Results

Gross-total resection (GTR) was performed in 41 (55%) of the 74 patients; subtotal resection ([STR]; 90–99%) in 25 (34%); and partial resection ([PR]; < 90%) in 8 (11%). Regrowth rates in the GTR, STR, and PR groups were 2.4% (1 of 41 cases), 52% (13 of 25), and 62.5% (5 of 8), respectively, and the times to regrowth ranged from 6 to 76 months (median 31.9 months). The regrowth-free survival curves differed significantly between the complete (GTR) and incomplete (STR and PR) resection groups. Eighteen (54.5%) of the 33 patients who underwent incomplete resection showed evidence of regrowth during follow-up. Univariate and multivariate analyses of various factors revealed that both the thickness of the residual tumor, based on MR imaging after surgery, and the MIB-1 index were positively related to residual tumor regrowth. The receiver operating characteristic curves, plotted for both the thickness of the residual tumor and the MIB-1 index, identified the optimal cutoff points for these values as 7.4 mm (sensitivity 83.3%, specificity 86.7%) and 1.6 (sensitivity 83.3%, specificity 66.7%), respectively.

Conclusions

Greater residual tumor thickness, based on MR imaging after the initial surgery, and a higher MIB-1 index are both important factors related to postoperative tumor regrowth in patients who have undergone incomplete VS resection. These patients require frequent neuroimaging investigation during follow-up to assure early detection of tumor regrowth.
A novel transnasal transsphenoidal speculum: a design for both microscopic and endoscopic transsphenoidal pituitary surgery
Authors: Chole Richard A. , Lim Chris , Dunham Brian , Chicoine Michael R. , Dacey Ralph G.
Published: January 2011

Over the last several years minimally invasive surgical approaches to the sella turcica and parasellar regions have undergone significant change. The transsphenoidal approach to this region has evolved from a sublabial transnasal, to transnasal, to pure endonasal approaches with the increasing popularity of endoscopic over microscopic techniques. Endoscopic and microscopic techniques individually or in combination have their own unique advantages, and the preference of one over the other awaits further technological refinements and surgical experience.

In parallel with this evolution in techniques for transsphenoidal surgery, the authors designed an adaptable versatile speculum for the endonasal/transnasal transsphenoidal approach to the sella turcica and parasellar regions that can be used equally effectively with a microscope or an endoscope. The development of this instrument and its unique features are described, and its initial clinical use is summarized.

This transnasal transsphenoidal speculum has interchangeable blades, unique blade angulations, and independent blade opening mechanisms and allows safe, optimal exposure in all patients regardless of the size and anatomical aberrations of individual nasal and endonasal regions. An attached endoscope carrier further allows it to be used interchangeably with microscopic or endoscopic techniques without having to remove the speculum; likewise, a single surgeon can use both hands without need of an assistant. A forehead headrest component adds further stabilization. This device has been used successfully in 90 transsphenoidal procedures.
Inhibition of glioma growth by microbubble activation in a subcutaneous model using low duty cycle ultrasound without significant heating
Authors: Burke Caitlin W. , Klibanov Alexander L. , Sheehan Jason P. , Price Richard J.
Published: January 2011

Object

In this study, the authors sought determine whether microbubble (MB) destruction with pulsed low duty cycle ultrasound can be used to reduce brain tumor perfusion and growth through nonthermal microvascular ablation.

Methods

Studies using C57BLJ6/Rag-1 mice inoculated subcutaneously with C6 glioma cells were approved by the institutional animal care and use committee. Microbubbles were injected intravenously, and 1 MHz ultrasound was applied with varying duty cycles to the tumor every 5 seconds for 60 minutes. During treatment, tumor heating was quantified. Following treatment, tumor growth, hemodynamics, necrosis, and apoptosis were measured.

Results

Tumor blood flow was significantly reduced immediately after treatment, with posttreatment flow ranging from 36% (0.00002 duty cycle) to 4% (0.01 duty cycle) of pretreatment flow. Seven days after treatment, tumor necrosis and apoptosis were significantly increased in all treatment groups, while treatment with ultrasound duty cycles of 0.005 and 0.01 inhibited tumor growth by 63% and 75%, respectively, compared with untreated tumors. While a modest duty cycle–dependent increase in intratumor temperature was observed, it is unlikely that thermal tissue ablation occurred.

Conclusions

In a subcutaneous C6 glioma model, MB destruction with low–duty cycle 1-MHz ultrasound can be used to markedly inhibit growth, without substantial tumor tissue heating. These results may have a bearing on the development of transcranial high-intensity focused ultrasound treatments for brain tumors that are not amenable to thermal ablation.
Dopamine agonist–resistant prolactinomas
Authors: Oh Michael C. , Aghi Manish K.
Published: January 2011

The authors' object in this paper was to review the definition, epidemiology, biology, resistance mechanisms, and treatment options for dopamine agonist–resistant prolactinomas (DARPs).

Prolactinomas are relatively unique among primary brain tumors in that medical treatment alone using dopamine agonists carries a high probability of disease control or even radiographic and endocrine remission, and thus has replaced surgery as the first line of therapy. Unfortunately, slightly less than 10% of patients with prolactinomas do not experience normalization of their prolactin levels in response to dopamine agonists, and harbor tumors that are resistant to dopamine agonist therapy. A literature review underscores that in male patients these DARPs are more likely to be invasive macroadenomas than dopamine agonist–responsive prolactinomas and that they are also more angiogenic, more proliferative, and more likely to exhibit cellular atypia. Estrogen receptor antagonists and temozolomide are the most commonly applied medical therapies in cases in which resection and radiosurgery have not induced remission of the hyperprolactinemia.

Dopamine agonist–resistant prolactinomas exhibit aggressive behavior and tend to be large, invasive, hyperangiogenic tumors with high mitotic indices, which makes their management via surgery, radiosurgery, or alternative medical therapies challenging, thus underscoring the need for novel medical therapies or treatment regimens that target these lesions.
Discrimination between low-grade oligodendrogliomas and diffuse astrocytoma with the aid of 11C-methionine positron emission tomography
Authors: Shinozaki Natsuki , Uchino Yoshio , Yoshikawa Kyosan , Matsutani Tomoo , Hasegawa Azusa , Saeki Naokatsu , Iwadate Yasuo
Published: January 2011

Object

The diagnostic usefulness of 11C-methionine PET scans in gliomas is still controversial. The authors investigated the clinical significance of 11C-methionine PET findings in preoperative diagnosis of histological type and grade.

Methods

The tissue uptake of 11C-methionine was assessed using PET in 70 patients with histologically confirmed intracerebral gliomas. The ratio of maximum standard uptake values in tumor areas to the mean standard uptake values in the contralateral normal brain tissue (tumor/normal tissue [T/N] ratio) was calculated and correlated with tumor type, histological grade, contrast enhancement on MR imaging, Ki 67 labeling index, and 1p/19q status.

Results

The T/N ratio was significantly increased as tumor grade advanced in astrocytic tumors (WHO Grade II vs Grade III, p = 0.0011; Grade III vs Grade IV, p = 0.0007). Among Grade II gliomas, the mean T/N ratio was significantly higher in oligodendroglial tumors than in diffuse astrocytomas (DAs) (p < 0.0001). All T/N ratios for oligodendroglial tumors were ≥ 1.46, and those for DA were consistently < 1.46, with the exception of 2 cases of gemistocytic astrocytoma. The Ki 67 labeling index significantly correlated with T/N ratio in astrocytic tumors, but not in oligodendrogliomas. Oligodendroglial tumors without 1p/19q deletion had a significantly higher T/N ratio than those with the codeletion. In combination with Gd-enhanced MR imaging, 67% of nonenhanced tumors with a T/N ratio of ≥ 1.46 were proved to be Grade II oligodendrogliomas.

Conclusions

These results clearly show that 11C-methionine PET T/N ratios in Grade II oligodendrogliomas were higher than those in DAs independently of their proliferative activity. This information contributes to preoperative differential diagnoses of histological type, especially in suspected low-grade gliomas.
Neurosurgical treatment of craniopharyngioma in adults and children: early and long-term results in a large case series
Authors: Mortini Pietro , Losa Marco , Pozzobon Gabriella , Barzaghi Raffaella , Riva Marco , Acerno Stefania , Angius Diana , Weber Giovanna , Chiumello Giuseppe , Giovanelli Massimo
Published: January 2011

Object

Craniopharyngioma accounts for 2%–5% of all primary intracranial neoplasms. The optimal management of craniopharyngioma remains controversial. The authors evaluated the early results of surgery and the longterm risk of tumor recurrence in a large series of patients undergoing resection of craniopharyngiomas.

Methods

Between 1990 and 2008, 112 consecutive patients (57 male and 55 female patients with a mean [± SEM] age of 33.3 ± 1.8 years) underwent resection of craniopharyngiomas at the authors' hospital. Recurrence or growth of residual tumor tissue during follow-up was assessed using MR imaging.

Results

There were 3 perioperative deaths (2.7%). Severe adverse events were more frequent in patients who underwent operations via the transcranial route (37%) than the transsphenoidal approach (5.6%; p < 0.001). Magnetic resonance imaging showed radical resection of the tumor in 78 (71.6%) of the remaining 109 patients. Previous surgery and maximum tumor diameter were associated with persistence of disease after surgery. Craniopharyngioma recurred in 26 (24.5%) of 106 patients. Presence of residual tumor on the first postoperative MR imaging, male sex, and no postoperative radiation therapy were associated with a risk of tumor recurrence. Quality-of-life data were assessed in the 91 patients who attended the authors' institution for follow-up visits. Among them, 8.8% patients were partially or completely dependent on others for daily living activities before surgery. This percentage increased to 14.3% at the last follow-up visit. The 5- and 10-year overall survival rates were 94.4% (95% CI 90.0%–98.8%) and 90.3% (95% CI 83.4%–97.3%), respectively.

Conclusions

Complete surgical removal of craniopharyngioma can be achieved with reasonable safety in more than 70% of patients. Recurrence of craniopharyngioma may occur even after apparent radical excision. Prompt management of residual or recurring disease by radiotherapy, repeat surgery, or a combination of both is usually successful in controlling further tumor growth.
Pleomorphic xanthoastrocytoma and oligodendroglioma: collision of 2 morphologically and genetically distinct anaplastic components
Authors: Hattab Eyas M. , Martin Sarah E. , Shapiro Scott A. , Cheng Liang
Published: January 2011

With the exception of oligoastrocytoma, mixed gliomas are rarely encountered, and the astrocytic component of mixed oligoastrocytoma is almost always fibrillary and diffusely infiltrative. Pleomorphic xanthoastrocytoma (PXA) has occasionally been described in conjunction with ganglioglioma, as well as in 1 case of oligodendroglioma. In this latter case, described by Perry et al., 1p/19q codeletions were not detected.

The authors report on a 25-year-old woman with a combined PXA/oligodendroglioma in which concurrent 1p/19q codeletions were detected in the oligodendroglial component only. The patient presented with a 1-month history of headaches. Neuroimaging revealed a heterogeneous left temporal mass with focal enhancement, cystic changes, hemorrhage, and left-to-right midline shift. The patient underwent a craniotomy and gross-total resection. Pathological examination revealed a glial tumor composed of 2 apparently distinct components. The largest component exhibited a prominent fascicular, reticulin-rich, spindle cell arrangement admixed with areas of highly pleomorphic cells, with bizarre cytological features reminiscent of PXA. A smaller component was composed of cellular sheets and lobules of oligodendroglial cells. Both components were characterized by anaplastic features. Dual-color fluorescence in situ hybridization for 1p/19q codeletions was performed. Only the oligodendroglial component showed the combined 1p/19q deletions.

This case represents the first instance in which PXA has been reported in conjunction with an oligodendroglioma exhibiting the “molecular signature” characteristic of oligodendroglial neoplasms. The different genetic alterations seen in the 2 components of this neoplasm argue in favor of a “collision tumor” rather than a mixed glioma of the same genotype.
Reflections on the contributions of Harvey Cushing to the surgery of peripheral nerves
Authors: Tubbs R. Shane , Patel Neal , Nahed Brian Vala , Cohen-Gadol Aaron A. , Spinner Robert J.
Published: January 2011

By the time Harvey Cushing entered medical school, nerve reconstruction techniques had been developed, but peripheral nerve surgery was still in its infancy. As an assistant surgical resident influenced by Dr. William Halsted, Cushing wrote a series of reports on the use of cocaine for nerve blocks. Following his residency training and a hiatus to further his clinical interests and intellectual curiosity, he traveled to Europe and met with a variety of surgeons, physiologists, and scientists, who likely laid the groundwork for Cushing's increased interest in peripheral nerve surgery. Returning to The Johns Hopkins Hospital in 1901, he began documenting these surgeries. Patient records preserved at Yale's Cushing Brain Tumor Registry describe Cushing's repair of ulnar and radial nerves, as well as his exploration of the brachial plexus for nerve repair or reconstruction. The authors reviewed Harvey Cushing's cases and provide 3 case illustrations not previously reported by Cushing involving neurolysis, nerve repair, and neurotization. Additionally, Cushing's experience with facial nerve neurotization is reviewed. The history, physical examination, and operative notes shed light on Cushing's diagnosis, strategy, technique, and hence, his surgery on peripheral nerve injury. These contributions complement others he made to surgery of the peripheral nervous system dealing with nerve pain, entrapment, and tumor.