Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae.

An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1ß and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future.

Anomalous recovery characteristics of Pd modified ZnO nanorod based acetone sensor.

Unmodified and Pd modified Zinc Oxide (ZnO) hexagonal nanorods, grown by Chemical Bath Deposition (CBD), is reported in this paper for efficient detection of acetone vapor. After details structural characterization (XRD, FESEM and AFM) the nanorod based sensors were tested in resistive mode for detection of acetone in the concentration range of - 190-3040 ppm. By Pd surface modification the optimum working temperature was brought down from 350 degrees C (unmodified) to 300 degrees C with appreciable improvement in response magnitude (90% to 99%) also. Strikingly, the recovery time, after Pd modification, became faster than the corresponding response time up to certain concentrations range (190-1530 ppm) and above this concentration (> or = 1530-3040 ppm) response time was found to be faster than recovery time which is similar to the case with unmodified nanorods (for entire concentration range). There are earlier reports on such faster recovery (compared to response), but no proper explanation was provided. In this paper we tried to explain this apparent anomaly of recovery characteristics through concentration dependent reaction rate variation following Arrhenius equations. Also a correlation between the parameters of the corresponding electrical equivalent circuit of the sensor has been established.

Detection of the membrane attack complex as a diagnostic tool in dermatomyositis.

BACKGROUND: Currently there is no reliable diagnostic marker to distinguish between the subgroups of idiopathic inflammatory myopathies (IIMs), i.e. dermatomyositis (DM), polymyositis (PM) and inclusion body myositis (IBM). Membrane attack complex (MAC) has been shown to be involved in the pathogenesis of dermatomyositis but its role as a diagnostic marker has not been evaluated. AIM: To assess the diagnostic utility of MAC deposition in distinguishing dermatomyositis from other neuromuscular disorders. MATERIAL AND METHODS: Immunohistochemical detection of MAC deposition on endomysial microvessels was carried out on 127 muscle biopsies comprising of 21 cases of dermatomyositis, 42 other IIMs and 64 non-IIM neuromuscular diseases. RESULTS: MAC deposition showed a high sensitivity (80.9%) and specificity (85%) to differentiate DM from other IIMs. Its specificity was higher (98.4%) in discriminating DM from non-IIM muscular diseases and IIM from non-IIMs. CONCLUSION: MAC deposition can serve as a reliable marker to distinguish DM from other IIMs (i.e. PM and IBM) as well as from non-IIM diseases. It can also serve as a useful adjunct in diagnosis of IIMs when there is diagnostic dilemma with their morphologic similarities. These results provide further credence to the long-standing view that MAC-mediated capillary destruction is involved in the immunopathogenesis of DM.

Congenital myopathies--a comprehensive update of recent advancements.

The congenital myopathies are relatively newly discovered compared with other categories of muscle diseases. Current research continues to clarify and classify the congenital myopathies. These pose a diagnostic problem and cannot be diagnosed by routine hematoxylin and eosin stain. A lot of special techniques are required to diagnose them correctly and it's various subtypes. The disease specific structural changes seen in the muscle are detected by enzyme histochemistry, immunohistochemistry and electron microscopy. Through this review we provide an up-to-date analysis of congenital myopathies including clinical and pathologic aspects.

Recurrent ependymoma with cartilaginous metaplasia in an adult: report of a rare case and review of literature.

Cartilaginous metaplasia in ependymomas is an uncommon phenomenon and is hypothesized to be due to metaplasia of the mesenchymal supportive elements or arising from the neoplastic glial cells. Most of the previous cases reported have occurred in children less than 10 years of age. The present report discusses an unusual case of ependymoma with cartilaginous metaplasia in a 21-year-old male. A brief review on the histogenesis of cartilaginous metaplasia is also provided.

Papillary tumor of the pineal region--a recently described entity: a report of three cases and review of the literature.

BACKGROUND: The papillary tumor of the pineal region (PTPR) is a distinct clinicopathologic entity, the exact biological behavior of which is not known. FINDING: In the present report we describe 3 additional cases of PTPR because of its rarity. During a study period of 4 years (between January 2003 and December 2006), we diagnosed three cases of papillary tumor of the pineal region (PTPR). Clinico-radio-pathologic examination was done and follow-up was assessed. Microscopically, all 3 cases showed uniform morphology and consisted of papillary and solid areas. Immunohistochemistry showed strong and diffuse positivity for synaptophysin, NSE, chromogranin A, S-100 protein, MAP-2 and cytokeratin. CONCLUSION: PTPR is a distinct entity and needs to be differentiated from other tumors of the pineal region as the biological behavior of this tumor is not fully understood. Radiologically this tumor can sometimes be misdiagnosed as tectal glioma.

Current concepts in the pathology and genetics of gliomas.

In recent years, there has been a marked improvement in our understanding of molecular genetics of gliomas. These advancements offer hope for development of tailored therapies targeting a tumor's unique molecular profile, and may also translate into improved classification and identification of newer prognostic markers. This review focuses on the neuropathological features of different types of glial neoplasms according to the World Health Organization classification, and the recent advances in their molecular biology with emphasis on the genetic mechanisms underlying tumor progression, diagnostic and prognostic markers and potential therapeutic targets.

Chordoid glioma: report of two rare examples with unusual features.

BACKGROUND: Chordoid glioma, a rare tumour of the third ventricle, represents a distinct clinico-pathologic entity. Thirty nine examples have been described in the literature, mostly in females and in the third ventricle. The clinical presentation is variable but they tend to occur mostly in adults. There is only one report of a chordoid glioma in a 12 year old child. FINDING: This paper describes two examples of chordoid glioma in a seven year old female child and a 70 year old male respectively. Radiologically, the paediatric chordoid glioma was located in the juxtaventricular region in the occipital horn of the lateral ventricle and was of mixed density whereas the adult patient had a typical third ventricle location with homogenous contrast enhancement. Gross total surgical removal was achieved in both but the adult patient died post-operatively due to intra ventricular bleeding and bacterial meningitis. The younger patient is doing well at the last follow up two years post-operatively. Microscopically, both showed the classic morphology of chordoid glioma. Ultrastructural examination was suggestive of ependymal differentiation. CONCLUSION: The younger age and unusual location are some of the rare features which need documentation and have not been described earlier. We propose that chordoid glioma is a variant of an ependymoma (WHO grade II) which arises from tanycytes and should be included in the WHO classification of brain tumors.

Surgical outcome of cortical dysplasias presenting with chronic intractable epilepsy: a 10-year experience.

BACKGROUND: There has been sparse description of cortical dysplasias (CDs) causing intractable epilepsy from India. AIM: Clinical retrospective study of CDs causing intractable epilepsy that underwent surgery. MATERIALS AND METHODS: Fifty-seven cases of CDs reviewed (1995 till July 2006) are presented. All patients had intractable epilepsy, and underwent a complete epilepsy surgery workup (inter ictal electroencephalography (EEG), video EEG, MRI as per epilepsy protocol, SPECT {interictal, ictal with subtraction and co-registration when required}, and PET when necessary). Surgical treatment included a wide exposure of the pathology with a detailed electrocorticography under optimal anesthetic conditions. Mapping of the sensori-motor area was performed where indicated. Procedures included resection either alone or combined with multiple subpial transactions when extending into the eloquent areas. RESULTS: Our study had 28 (49.12%) cases of isolated focal CDs, and 29 (50.67%) with dual pathology. Average age at the time of onset of seizures in our series was 7.04 years (three months to 24 years), and average age at the time of surgery was 10.97 years (eight months to 45 years). Among coexistent pathologies, one had associated MTS, 16 had coexistent gangliogliomas and 12 (dysembryonic neuroepithelial tumor) DNTs. At an average follow-up of 3.035 years (range 5-10 years), three patients were lost to follow-up. Fifty-one per cent (29/57) patients had a good outcome (Engel Grade I) and 26%(15/57) had a Grade II outcome. CONCLUSION: Cortical dysplasias have a good outcome if evaluated and managed with concordant electrical and imaging modalities.

Multi-minicore disease: a rare form of myopathy.

BACKGROUND: Multi-minicore disease is a rare form of myopathy characterized by slowly progressive or nonprogressive muscle weakness and characteristic multiple cores within the muscle fibers. To the best of our knowledge, this is first documentation of the clinicopathological features of this rare entity from India. MATERIALS AND METHODS: A ll cases of multi-minicore disease diagnosed in our laboratory were retrieved. Clinical and pathological features were reviewed. RESULT: During a period of two years (January 2004 to December 2005), we received 985 muscle biopsies for various reasons. Of which, 15 were diagnosed as myopathies and four of which were of multi-minicore disease. Thus, multi-minicore disease comprises 0.40% of all muscle diseases and 26.6% of all myopathies. All were male and presented in early childhood (first decade of life) with generalized hypotonia and muscle weakness. All of them had dysmorphic facies and three had high arched palate. CPK levels were normal and EMG was myopathic except in one patient. Microscopic examination revealed minimal changes with Type I fibers' predominance but characteristic multiple cores in the myofibers. Ultrastructural examination showed both structured and unstructured cores. CONCLUSIONS: Multi-minicore disease, although a rare form of myopathies, should be suspected in children who present with generalized hypotonia and slowly progressive muscle weakness along with dysmorphic facies.

Nemaline rod myopathy: a rare form of myopathy.

Nemaline rod myopathy (NM) is a rare form of congenital myopathy characterized by slowly progressive or nonprogressive muscle weakness and pathognomonic rod-like structures within the muscle fibers. To the best of our knowledge, this is first documentation of the clinicopathological features of this rare entity from India. All cases of NM diagnosed in our laboratory were retrieved. Clinical and pathological features were reviewed. During a period of 1.5 years (Jan 2004 to June 2005), we received 750 muscle biopsies for various reasons. Of which, 15 were diagnosed as congenital myopathies and four as nemaline rod myopathies. Thus, NM comprises 0.53% of all muscle diseases and 22.6% of all congenital myopathies. All of them presented in childhood (first five years of life) with generalized hypotonia, feeding problems, repeated respiratory infections and muscle weakness. Both males and females were equally affected. The CPK levels were normal and EMG was myopathic. Microscopic examination revealed minimal changes but characteristic red-colored material was seen on modified Gomori trichrome staining which was immunopositive to alpha actinin. Ultrastructural examination confirmed this material to be nemaline rods. NM, although a rare form of congenital myopathies, should be suspected in children who present with generalized hypotonia, repeated chest infections and slowly progressive muscle weakness. This report highlights the importance of histochemistry and ultrastructural examination in the diagnosis of this entity, in the absence of the availability of methodology for genetic studies.

Poorly differentiated thyroid carcinoma with rhabdoid phenotype: a diagnostic dilemma--report of a rare case.

Rhabdoid tumor is a distinct entity reported in renal and extrarenal sites. Malignant tumors of various types may have rhabdoid phenotype. There are eight case reports of carcinomas of thyroid with rhabdoid phenotype. All of these cases, except two, have been reported in middle-aged women (42-72 yr) and have had an aggressive clinical course with death occurring within few months to 4 yr after diagnosis. We report a case of poorly differentiated carcinoma of the thyroid with rhabdoid phenotype in a 22-yr-old male. The rhabdoid cells were immunopositive for thyroid transcription factor-1, vimentin, epithelial membrane antigen, and focally for cytokeratin. Synaptophysin, chromogranin, thyroglobulin, carcinoembryonic antigen, smooth muscle actin, myogenin, and desmin were all negative. To the best of our knowledge this is the ninth case report of carcinoma of the thyroid with rhabdoid phenotype. This case, unlike the previous reported cases, has certain unusual features including presentation in a young male, the absence of either follicular/papillary differentiation, and immunohistochemical profile of the rhabdoid cells.

Nrf2-driven TERT regulates pentose phosphate pathway in glioblastoma.

Given the involvement of telomerase activation and dysregulated metabolism in glioma progression, the connection between these two critical players was investigated. Pharmacological inhibition of human Telomerase reverse transcriptase (hTERT) by Costunolide induced glioma cell apoptosis in a reactive oxygen species (ROS)-dependent manner. Costunolide induced an ROS-dependent increase in p53 abrogated telomerase activity. Costunolide decreased Nrf2 level; and ectopic Nrf2 expression decreased Costunolide-induced ROS generation. While TERT knock-down abrogated Nrf2 levels, overexpression of Nrf2 increased TERT expression. Inhibition of hTERT either by Costunolide, or by siRNA or dominant-negative hTERT (DN-hTERT) abrogated (i) expression of Glucose-6-phosphate dehydrogenase (G6PD) and Transketolase (TKT) - two major nodes in the pentose phosphate (PPP) pathway; and (ii) phosphorylation of glycogen synthase (GS). hTERT knock-down decreased TKT activity and increased glycogen accumulation. Interestingly, siRNA-mediated knock-down of TKT elevated glycogen accumulation. Coherent with the in vitro findings, Costunolide reduced tumor burden in heterotypic xenograft glioma mouse model. Costunolide-treated tumors exhibited diminished TKT activity, heightened glycogen accumulation, and increased senescence. Importantly, glioblastoma multiforme (GBM) patient tumors bearing TERT promoter mutations (C228T and C250T) known to be associated with increased telomerase activity; exhibited elevated Nrf2 and TKT expression and decreased glycogen accumulation. Taken together, our findings highlight the previously unknown (i) role of telomerase in the regulation of PPP and glycogen accumulation and (ii) the involvement of Nrf2-TERT loop in maintaining oxidative defense responses in glioma cells.

Infrequent alteration of the c-myc gene in human glial tumours associated with increased numbers of c-myc positive cells.

Twenty five human glial tumours of different grades of malignancy were examined by Southern blotting and polymerase chain reaction (PCR) for alterations (rearrangements, amplification and deletions) in the c-myc gene. Number of c-myc positive cells per thousand cells were also counted in all the tumours after immunohistochemical staining for c-myc protein was done on fixed sections of the tumours. No tumours exhibited any amplification of the gene, as found by Southern blotting. One astrocytoma and one mixed glioma showed some rearrangements in the 3' end of the gene, as detected by Southern blotting and hydridization. These two tumours had higher number of c-myc positive cells than in other tumours of the same histopathological groups. Deletion in the first promoter region, as determined by PCR, was seen in only one astrocytoma. However, the number of c-myc positive cells in that tumour did not show any deviation from that found in other astrocytomas. In light of present literature, it is speculated that the 3' rearrangements may be the cause of increased number of c-myc immunopositive cells in those tumours by disrupting the 3' end of the gene leading to increased c-myc mRNA stability. Such a mechanism may play a part in small subset of glial and possibly other tumours.

Loss of heterozygosity of a locus on 17p13.3, independent of p53, is associated with higher grades of astrocytic tumours.

Amongst the human astrocytic tumours, the commonest of primary brain tumours, the clinical outcome of astrocytoma (AS) is significantly better than anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM). Often, low grade tumours can progress to or recur with a more malignant phenotype. Recent loss of heterozygosity (LOH) reports suspect the involvement of a tumour suppressor gene, different from p53, in the 17p13.3 region of the human chromosome. However, the effect of LOH of 17p13.3 region on tumour histology at presentation and prognosis is as yet undefined. As a first step to define the role of this putative oncogene in astrocytic tumour progression, we correlated the LOH of a locus, D17S379, in 17p13.3 region and the p53 locus in 17p13.1 region with the histopathology of astrocytic tumours by PCR based microsatellite and restriction fragment length polymorphism of DNA extracted from microdissected paraffin sections of 45 astrocytic tumours of different histopathological grades. LOH of D17S379 was significantly associated (P=0.02) with AA and GBM (high grade malignancy), while no such preferential association was found with LOH of p53. There were no mutations in the exons 5 to 9 of p53 gene in the five tumours with LOH of D17S379 but not of p53 region. In a case of AA with a heterogenous microscopic appearance, heterozygosity of D17S379 was lost only in the area with a more malignant histology while both areas had no LOH or mutation of p53. A locus at the 17p13.3 region, independent of the p53 locus, is involved in a large subset of astrocytic tumours during transformation into a more malignant phenotype, and thus may be a link in the chain of genetic events occurring in astrocytic tumour progression.

Gangliosides in normal and cataractous lenses of several species.

The present study was undertaken to compare the content, composition and distribution of gangliosides in ocular lenses of different species, both normal and cataractous. Gangliosides were extracted from cow, pig, rat and human lens by either the Folch-Suzuki partition procedure or by the modified tetrahydrofuran procedure. Between 20 and 45% more ganglioside was recovered from lenses by the tetrahydrofuran than the Folch-Susuki partition procedure. Cow, pig, rat and human normal lens extracted by the tetrahydrofuran procedure contained, respectively, 24.8, 22.3, 71.2, and 272.5 micrograms of ganglioside sialic acid/g lens (wet wt.). No protein-bound sialic acid was detected in any lens. No significant differences were observed in the content or composition of gangliosides from normal and cataractous human lens and from cataractous rat lens induced by the drug U18666A. Although hematoside (GM3) was the predominant ganglioside in bovine (73%) and pig (68%) lens, small amounts of what appeared to be GM1, GD1a, and GT1 were also detected. GM1 predominated (95%) in rat lens, with the remainder being GM3. This is apparently the highest relative content of GM1 reported in a non-neural tissue. Human lens contains two gangliosides, GM1 (53%) and GM3 (47%). Examination of the distribution of gangliosides between various regions of the bovine lens revealed that the epithelial cell fraction contained an about 10 times higher concentration of total gangliosides than either the lens cortex or nucleus.

Primary AL (kappa-light chain) amyloidosis manifesting as peripheral neuropathy in a young male without increase in serum and urine immunoglobulin load: a diagnostic challenge.

Primary systemic or AL amyloidosis is a multisystem disorder characterized by diffuse extracellular infiltration of a fibrillar protein of monoclonal light chain origin (AL). Majority of the patients have monoclonal immunoglobulin in serum and/or urine and some have clonal proliferation of plasma cells in their bone marrow. This disease has the widest spectrum of organ involvement, most commonly affecting the kidneys, heart and liver. Involvement of peripheral nervous system is not infrequent and may be the presenting feature of the disease process. Thus, recognition of peripheral neuropathy and affecting the kidney as an early symptom of AL amyloidosis may widen the scope for therapeutic intervention. We describe here a rare case of primary amyloidosis (AL) kappa-light chain presenting with clinical features of peripheral neuropathy and affecting the kidney and heart at an early age of 18 years, hitherto unreported in literature. The case was further interesting as it was not associated with increased serum/urine immunoglobulins or plasma cells in bone marrow. Diagnosis was confirmed using immuno-electron microscopy on sural nerve biopsy.

Desmin-related myopathy: report of a rare case.

The Protein Surplus Myopathies (PSM) are characterized by accumulation of protein aggregates, identifiable ultrastructurally, resulting due to mutations of the encoding genes. Desmin-related myopathies (DRM) are a form of PSM characterized by mutations of the desmin gene resulting in the formation of protein aggregates comprising mutant protein desmin and disturbance of the regular desmin intermediate network in the muscle fibers. We describe a rare case of DRM in a 23-year-old man who presented with complaints of difficulty in climbing stairs and running since the age of 5 years. EMG studies revealed a myopathic pattern. Muscle biopsy showed the features of muscular dystrophy with bluish rimmed vacuoles and sarcoplasmic inclusions, which were immunoreactive to desmin. Ultrastructural examination showed sarcoplasmic bodies and granulofilamentous inclusions. Although rare, the possibility of DRM/desminopathy should be considered in the presence of bluish rimmed vacuoles on light microscopy and characteristic ultrastructural inclusions. To the best of our knowledge this is the first case of DRM/desminopathy reported from India.