Segmental polymethylmethacrylate-augmented fenestrated pedicle screw fixation for lumbar spondylolisthesis in patients with osteoporosis - A case series and review of literature.

BACKGROUND: Instrumentation in patients with osteoporosis is challenging. Bone cement-augmented fenestrated pedicle screw fixation is a new procedure for fixation in osteoporotic bone. Very few studies related to this procedure are published in literature. AIMS: To evaluate the clinical and radiological outcome of polymethylmethacrylate (PMMA)-augmented fenestrated pedicle screw fixation in patients with spondylolisthesis having significant osteoporosis. SETTINGS AND DESIGN: This was a prospective, observational, single centre study. MATERIALS AND METHODS: All the patients with lumbar spondylolisthesis and osteoporosis with symptomatic neural compression, managed surgically with PMMA-augmented fenestrated pedicle screws, were included in the study. Patients were evaluated preoperatively and postoperatively by means of Oswestry disability index (ODI), visual analog score (VAS); and, radiologically by plain radiography and computed tomography. STATISTICAL ANALYSIS: Wilcoxon nonparametric test for paired samples with a level of significance of 0.05 was performed. RESULTS: A total of 25 patients of spondylolisthesis with osteoporosis (average T score of -3.0) were included in the study. The average age at presentation was 56.5 years. Females predominated with a female:male ratio of 3.16:1.Most of the patients had spondylolisthesis at the L4/L5 level followed by the L5/SI level. All the patients underwent spinal fusion with instrumentation and bone cement (PMMA)-augmentation through fenestrated cannulated pedicle screws. Preoperative and postoperative functional assessment done with VAS and ODI showed statistically significant improvement. All the patients had an evidence of bone fusion at follow-up. CONCLUSION: Fenestrated pedicle screw fixation with bone cement-augmentation in patients with lumbar spondylolisthesis and osteoporosis provided effective and lasting screw purchase.

An algorithmic approach for clinical management of low back pain.

BACKGROUND: Low back pain is caused by a variety of conditions. When conventional imaging failed, single-photon emission computed tomography (SPECT) was superior to scintigraphy in identifying the pathology. Injection therapies are often helpful in treating the pathology. AIM: To determine the cause of chronic low backache in individuals with normal conventional imaging (radiographs, computed tomography and magnetic resonance imaging), to determine the specific pathology using scintigraphic studies and diagnostic blocks; and, to treat the individuals with various spinal injection techniques and determine their efficacy. MATERIAL AND METHODS: All the patients having chronic back pain on presentation in the outpatient clinic from April 2013 to October 2014 were prospectively evaluated. RESULTS: The 40 patients included in the study were followed up pre- and post operatively with various pain scales (visual analogue scale [VAS], Oswestry disability index [ODI] and short form health survery 36 [SF36]). The mean age at presentation was 41.3 years. Female patients formed the predominant subgroup in the study (57.5% female and 42.5% male patients). Pain indices like VAS and ODI were helpful in assessing the efficacy of spinal injections. Preoperative and postoperative pain scale assessment, supplemented by a SPECT evaluation of the sacroiliac and facet joints, showed a statistically significant difference, which correlated with clinically significant pain relief. CONCLUSIONS: SPECT imaging is helpful in diagnosing sacroiliac joint syndrome and facetal syndrome. Epidural injections were a better choice in cases of low backache, where clinically, the patient had no signs of sacroiliac joint syndrome and facetal syndrome. Spinal injections with steroid and local anaesthetic had better relief. Radiotracer uptake at the pain generating area is a good predictor of outcome. Image guided spinal injection improves the accuracy of the injection.

Clinical, radiological, and functional evaluation of surgical treatment in degenerative lumbar canal stenosis.

BACKGROUND: Lumbar spinal stenosis is a frequent indication for spinal surgery. The clinical symptoms may not be accurately reflected on radiological studies. Treatment is aimed at not only obtaining immediate pain relief but also in preventing its long-term disabling sequelae. The walking ability needs to be correlated with functional outcome measures in assessing patients with symptomatic lumbar canal stenosis (LCS). AIMS AND OBJECTIVES: To study and evaluate the outcome of surgery for degenerative LCS on a clinical, radiological, and functional basis, and to establish an association between various factors that may be influencing the development of LCS. MATERIALS AND METHODS: A prospective study of 48 patients was carried out at the Department of Neurosurgery, Sri Venkateswara Institute of Medical Sciences, Tirupathi, in whom the LCS was confirmed and measured on magnetic resonance imaging images by thecal sac cross-sectional area (CSA). Their functional assessment was done by motorized treadmill test for assessment of the time of appearance of first symptom and the maximum walking distance. The visual analog scale (VAS), Oswestry disability index (ODI), Japanese Orthopedic Association (JOA) score, and Short Form-36 (SF-36) score were also evaluated. CONCLUSIONS: The post-operative VAS, ODI, JOA, SF-36 scores showed a significant improvement from the preoperative ones. Postoperative thecal sac measurements showed a significant neural decompression substantiating the results of improvement in the functional assessment scores after surgery. The treadmill test is a quantifiable means of dynamic function. It may be considered as a useful tool for the assessment of functional impairment and for the correlation of thecal sac CSA with lumbar canal stenosis. A combination of functional scores, treadmill test, and thecal sac CSA may be included in the preoperative assessment of outcome in patients with LCS.

Functional analysis and binding affinity of tomato ethylene response factors provide insight on the molecular bases of plant differential responses to ethylene.

BACKGROUND: The phytohormone ethylene is involved in a wide range of developmental processes and in mediating plant responses to biotic and abiotic stresses. Ethylene signalling acts via a linear transduction pathway leading to the activation of Ethylene Response Factor genes (ERF) which represent one of the largest gene families of plant transcription factors. How an apparently simple signalling pathway can account for the complex and widely diverse plant responses to ethylene remains yet an unanswered question. Building on the recent release of the complete tomato genome sequence, the present study aims at gaining better insight on distinctive features among ERF proteins. RESULTS: A set of 28 cDNA clones encoding ERFs in the tomato (Solanum lycopersicon) were isolated and shown to fall into nine distinct subclasses characterised by specific conserved motifs most of which with unknown function. In addition of being able to regulate the transcriptional activity of GCC-box containing promoters, tomato ERFs are also shown to be active on promoters lacking this canonical ethylene-responsive-element. Moreover, the data reveal that ERF affinity to the GCC-box depends on the nucleotide environment surrounding this cis-acting element. Site-directed mutagenesis revealed that the nature of the flanking nucleotides can either enhance or reduce the binding affinity, thus conferring the binding specificity of various ERFs to target promoters.Based on their expression pattern, ERF genes can be clustered in two main clades given their preferential expression in reproductive or vegetative tissues. The regulation of several tomato ERF genes by both ethylene and auxin, suggests their potential contribution to the convergence mechanism between the signalling pathways of the two hormones. CONCLUSIONS: The data reveal that regions flanking the core GCC-box sequence are part of the discrimination mechanism by which ERFs selectively bind to their target promoters. ERF tissue-specific expression combined to their responsiveness to both ethylene and auxin bring some insight on the complexity and fine regulation mechanisms involving these transcriptional mediators. All together the data support the hypothesis that ERFs are the main component enabling ethylene to regulate a wide range of physiological processes in a highly specific and coordinated manner.

Characterization of capsaicin synthase and identification of its gene (csy1) for pungency factor capsaicin in pepper (Capsicum sp.).

Capsaicin is a unique alkaloid of the plant kingdom restricted to the genus Capsicum. Capsaicin is the pungency factor, a bioactive molecule of food and of medicinal importance. Capsaicin is useful as a counterirritant, antiarthritic, analgesic, antioxidant, and anticancer agent. Capsaicin biosynthesis involves condensation of vanillylamine and 8-methyl nonenoic acid, brought about by capsaicin synthase (CS). We found that CS activity correlated with genotype-specific capsaicin levels. We purified and characterized CS ( approximately 35 kDa). Immunolocalization studies confirmed that CS is specifically localized to the placental tissues of Capsicum fruits. Western blot analysis revealed concomitant enhancement of CS levels and capsaicin accumulation during fruit development. We determined the N-terminal amino acid sequence of purified CS, cloned the CS gene (csy1) and sequenced full-length cDNA (981 bp). The deduced amino acid sequence of CS from full-length cDNA was 38 kDa. Functionality of csy1 through heterologous expression in recombinant Escherichia coli was also demonstrated. Here we report the gene responsible for capsaicin biosynthesis, which is unique to Capsicum spp. With this information on the CS gene, speculation on the gene for pungency is unequivocally resolved. Our findings have implications in the regulation of capsaicin levels in Capsicum genotypes.

Isolated Rosai Dorfman disease of the central nervous system presenting as dural-based and intraparenchymal lesions.

OBJECTIVE: To report three patients with isolated Rosai Dorfman disease of the central nervous system. CASE REPORTS: We report two patients with dural-based lesions diagnosed imageologically as meningiomas, and one patient with multiple intraparenchymal lesions diagnosed imageologically as lymphoma. Two patients were males and one was female. All were above 35 years of age with no nodal or other system involvement. The diagnosis was established on surgically excised masses during histopathology. One patient died due to unrelated causes 10 years later and the other two are symptom-free at 21.5- and 11.5-year-follow-up. CONCLUSIONS: Awareness of the entity and consideration in the differential diagnosis of dural-based/intraparenchymal lesions is necessary for diagnosis and prognosis.

In vitro clonal propagation of bird eye chilli (Capsicum frutescens Mill.).

An efficient and highly reproducible protocol for micropropagation of bird eye chilli Capsicum frutescens was attempted. Murashige and Skoog (MS) medium containing 0.5-3.0 mgl(-1) of 6-benzyladenine (BA), 2-isopentenyl adenine (2iP), kinetin and 0.5-2.0 mg l(-1) of indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) along with 1 gl(-1) activated charcoal (AC) were used for shoot regeneration from both shoot tip and nodal explants. Shoot tip explants (100%) grew well on medium containing 1 mgl(-1) of kinetin and 1 mgl(-1) of IBA. Shoot proliferation (1-3) from nodal explants was effective on this medium. The regenerated shoots with 4-7 nodes had further growth upon sub-culturing onto kinetin (1 mgl(-1)) and IBA (1 mgl(-1)) and rooted simultaneously. The rooted plants were transferred to pots after hardening under controlled conditions. The survival percentage in pots was 80-90%.

Brain abscess due to Entamoeba histolytica.

A patient of cerebral amoebiasis due to Entamoeba histolytica with no evidence of disease elsewhere is described. He made a complete recovery after surgical excision of the abscess along with metronidazole therapy.

Food utilization efficiency in fifth instar larvae of Antheraea mylitta (Lepidoptera: Saturniidae) infected with Nosema sp. and its effect on reproductive potential and silk production.

Antheraea mylitta, a sericigenous insect of economical importance is often infected with an intracellular parasite of the genus Nosema. This pathogen is known to cause fatal pebrine disease and is considered as an important factor that strongly influences the development of the host. Larvae developed from the eggs laid by a female infected with Nosema sp. showed extended development period. The increment in the larval weight declined significantly in infected larvae in comparison to uninfected ones. Food consumption, digestion, relative consumption rate (RCR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and relative growth rate (RGR) values declined significantly, but at the same time a significant increase in approximate digestibility (AD) was also observed. Silk production declined in infected larvae. Silk gland weight and shell weight also significantly declined following infection over uninfected larvae. The reproductive potential in adults declined significantly (P<0.001) with decrease in ovary weight (31.6%), fecundity (54.1%), and fertility (34.9%). Egg chorionation was also affected in adults, which developed from infected larvae. The maternal infection level in one generation (10.4 x 10(6) spores/female) decreased significantly in the next generation (8.0 x 10(6) spores/female).

Chemosensation: molecular mechanisms in worms and mammals.

Communication with the environment and other animals through chemical cues is an essential process for the survival of many multicellular organisms. Specialized signal transduction pathways are employed in chemodetection and the transformation of information into the electrical signals that elicit behaviors. In organisms as diverse as mice and nematodes, similar molecules are involved in the odorant signaling pathways. Studying the mechanisms of signal transduction in these two systems using biochemical, molecular and genetic approaches has elucidated pathways for odor perception and the roles of specific proteins and second messenger molecules in the signaling cascades.

unc-3, a gene required for axonal guidance in Caenorhabditis elegans, encodes a member of the O/E family of transcription factors.

The expression of specialized signal transduction components in mammalian olfactory neurons is thought to be regulated by the O/E (Olf-1/EBF) family of transcription factors. The O/E proteins are expressed in cells of the olfactory neuronal lineage throughout development and are also expressed transiently in neurons in the developing nervous system during embryogenesis. We have identified a C. elegans homologue of the mammalian O/E proteins, which displays greater than 80% similarity over 350 amino acids. Like its mammalian homologues, CeO/E is expressed in certain chemosensory neurons (ASI amphid neurons) throughout development and is also expressed transiently in developing motor neurons when these cells undergo axonal outgrowth. We demonstrate that CeO/E is the product of the unc-3 gene, mutations in which cause defects in the axonal outgrowth of motor neurons, as well as defects in dauer formation, a process requiring chemosensory inputs. These observations suggest that the O/E family of transcription factors play a central and evolutionarily conserved role in the expression of proteins essential for axonal pathfinding and/or neuronal differentiation in both sensory and motor neurons.

Giant syringobulbia in childhood.

A case of giant syringobulbia with syringomyelia extending to the upper dorsal region is reported. The case occurred in a 3.5-year-old girl who presented with a history of frequent bouts of severe pain in the lower neck and the shoulder blades. Simple decompression of the syrinx by open myelotomy resulted in prompt relief and reversal of symptoms.

Intraspinal tumour presenting as hydrocephalus in childhood.

A case of cervical intramedullary spinal cord tumour presenting with hydrocephalus is reported for its rarity. Possible aetiopathologies and the relevant literature are reviewed.

Neuro-radiology of skeletal fluorosis.

Though fluorosis is prevalent in certain geographic parts of the world, it is likely to occur in other parts due to industrial intoxication and also in people with latent kidney disease even when they consume relatively lower amounts of fluoride than in endemic regions. A sizeable number of patients suffering from ossified posterior longitudinal ligament (OPLL) may have fluoride intoxication as the underlying cause. The clinical, radiologic and pathologic manifestations of OPLL in non-orientals have been reported to be very similar to those in orientals. The question whether all these entities reported from different ecospheres of the globe have common aetiological factors is worthy of further research. Though plain radiology shows the characteristics of fluorosis, CT and MR imaging modalities are very helpful in early diagnosis and also in planning proper surgical intervention.

Unusual non-osseous compression at the craniovertebral junction--a report of four cases.

A variety of congenital and acquired non-osseous compression elements at the craniovertebral junction have been known and a fibrous band among them is unusual. Unaccompanied by any bony abnormality, non-osseous compression due to thickened epidural tissue, possibly congenital, presenting in adulthood is described in four cases. The onset of symptoms was in the fourth and sixth decades. Three were males and one was a female. The clinical picture was a slowly progressive spastic quadriparesis except in the only female patient who developed sudden quadriplegia while carrying a weight over her head. MR tomography was diagnostic while CT scan ruled out any bony pathology. Release of the localised epidural constriction was performed in all; in one transorally. Good recovery ensued postoperatively while histopathology excluded infective or neoplastic pathology.