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Biomedical subjects

A Bhatia

Publications and source records attributed to A Bhatia.

At least 55 records · Page 3Linked to original sources

Isolation, characterization and disruption of the casein kinase II alpha subunit gene of Leishmania chagasi.

To elucidate the role played by casein kinase II in Leishmania survival, we have isolated and characterized the Leishmania chagasi casein kinase II alpha subunit cDNA, (L.c CKIIalpha). The 1083 bp coding region is flanked by 148 bp of 5' UTR and 1155 bp of 3' UTR. L.c CKIIalpha shows a remarkable degree of similarity with other isolated casein kinase II alpha subunit sequences. L.c CKIIalpha protein is encoded by a single copy gene that transcribes a mRNA of 2.4 kb. The 41.2 kDa L.c CKIIalpha protein expressed in vitro has been shown to be catalytically active. A single allele disruption of the L.c CKIIalpha gene that removes 94 bp from the coding region which contains one of the 15 conserved amino acids closest to the carboxy-terminus of the protein has been generated. This mutant is viable and results in a reduction of L.c CKIIalpha transcript levels over 14-fold and that of an iron superoxide dismutase mRNA by 5-fold. As well, the kinase activity of the single allele disrupted cells showed a 3-fold reduction as compared to the wild type cells suggesting a decrease in activity of the L.c CkIIalpha enzyme.

Alleles↗

Histomorphometry of the ulnar nerve and of its branches.

A morphometric study has shown that 10% of the fibers of the ulnar nerve should suffice to reinnervate the biceps muscle in brachial plexus palsies. The aim of this study was to evaluate, by a morphometric study using computerized microanalysis, the cross-sectional surface areas of the different collateral and terminal branches of the ulnar nerve. This was expressed in terms of percentage of the cross-sectional surface area of the main trunk of the ulnar nerve. The study revealed that the branch to the flexor digitorum profundus bellies to the ring and little fingers formed 9.5% of the cross-sectional area of the ulnar nerve. Thus use of these fascicles destined for the flexor digitorum profundus, identified by intra-operative nerve stimulation, at the level of the arm would be sufficient for neurotisation of the nerve to the biceps. This has been confirmed by the initial clinical results in patients operated upon using this technique.

Aged↗

Differential distribution of Fc gamma RIIIa in normal human tissues and co-localization with DAF and fibrillin-1: implications for immunological microenvironments.

Fc gamma RIIIa is a cytokine-inducible IgG Fc receptor implicated in the activation of macrophages by immune complexes. Differential expression of Fc gamma RIIIa by macrophages in different tissues may therefore modulate local immune responsiveness. Fc gamma RIIIa expression in normal human tissues was assessed semiquantitatively using microdensitometry. Synovial intimal, serosal, alveolar, salivary gland and placental macrophages, Kupffer cells, and macrophages in mechanically stressed dermis expressed high levels of Fc gamma RIIIa. Less consistent expression was seen in skeletal muscle and lymphoid organs. No significant expression was observed in brain, thyroid, spine, intestine, myocardium, prostate, uterus, flexor forearm dermis, uterus, or kidney. Staining for Fc gamma RIII was also observed on extracellular matrix, and co-localized with both complement decay-accelerating factor and fibrillin-1. It is proposed that differential levels of both cellular and extracellular Fc gamma RIIIa, by modulating the response to immune complexes, may contribute to relative tissue susceptibility to infection and autoimmune disease.

CD55 Antigens↗

Nodular post-kala-azar dermal leishmaniasis: a distinct histopathological entity.

Post-kala-azar dermal leishmaniasis (PKDL) is an infrequently occurring sequel to treated visceral leishmaniasis. Diagnosis, particularly in non-endemic areas, is difficult because the clinical appearances may be subtle and simulate lepromatous leprosy. The histopathology of the condition has been a neglected subject. Nodular lesions constitute one of the large variety of lesions that can be seen in PKDL. This paper describes the histopathology of such lesions in 26 patients seen over a period of approximately 8 years in a non-endemic setting. All the biopsies had strikingly similar light microscopic features with characteristic findings: a dense lymphohistiocytic infiltrate beneath an atrophic epidermis, pronounced follicular plugging, vascular hyalinization and collagen changes and negative Fite stain. These allow a definite diagnosis of PKDL even in the absence of demonstrable Leishman-Donovan (L-D) bodies.

Biopsy↗

Fine-needle aspiration cytology of lepromatous leprosy.

A prospective study correlating cytopathology with clinical morphology and histopathology in 22 patients with lepromatous leprosy was performed. Aspirates were taken from skin lesions in all patients. Lymph node aspirates were also performed in four patients with lymphadenopathy. Fine-needle aspirates yielded sufficient cellular material with excellent preservation of morphological detail. Diagnosis and correlation with bacillary index, clinical and histopathological findings was possible in all patients. In addition, the two patterns, partial and diffuse, of lymph node involvement could be recognized. Fine-needle aspiration cytology is a simple method for the laboratory assessment of leprosy.

Biopsy, Needle↗

Cytomorphological features, AgNOR counts and c-erb B-2 in carcinoma breast.

The present study was designed to evaluate the cytomorphological features (nuclear grade and smear pattern) and AgNOR counts in 60 cases of carcinoma breast. The smears were stained with May Gruenwald Giemsa (MGG) and Papanicolaou stains. Silver staining nucleolar organiser region (AgNOR) counts and c-erb B-2 immunostaining were also done in each case. The smear pattern was assessed and classified as 'typical', 'cluster predominant' or 'individual cell type', and the nuclei were graded as grade I, II or III. Smear pattern and nuclear grade were found to be related variables. A significant association was found between nuclear grade and AgNOR counts (p = 0.03). Also postmenopausal women had statistically significant higher nuclear grades and less cohesive cell clusters as compared to premenopausal women. Twenty-three carcinoma breast were positive for c-erb B-2, of these 14 were postmenopausal women.

Adult↗

Screening for domestic violence in the emergency department.

The objective of this study was to determine whether two brief screening questions at the time of emergency department triage can increase the detection of domestic violence. Two questions concerning domestic violence were asked by emergency department personnel (registered nurses, licensed practising nurses, physician assistants) to all adult patients presenting to an urban level one trauma centre from 1 January 1993 to 31 December 1993. Patients were excluded if they were in extremis, or active labour. All potential abused patients were referred to a social worker for verification and intervention. A total of 59,405 patients were seen during the study period, and (79%) 46,929 participated. Of these, 132 (0.3%) total cases of domestic violence were identified. Of these 132 cases, 123 (93%) of them were available for follow-up and social worker intervention. Of these 123 cases, 17 (14%) were identified by the initial screening questionnaire. Screening questions concerning domestic violence can identify a small number of otherwise occult cases. Simply asking about domestic violence by emergency department triage personnel is insufficient. Further study is needed to identify the presumed greater number of unrecognized cases.

Adolescent↗

Cloning, characterization and overexpression of two iron superoxide dismutase cDNAs from Leishmania chagasi: role in pathogenesis.

We have isolated and characterized two superoxide dismutase (SOD) cDNAs from a Leishmania chagasi promastigote cDNA library using degenerate primers derived from conserved amino acid residues of previously isolated manganese and iron SODs. Comparison of these two L. chagasi SOD deduced amino acid sequences with previously isolated MnSOD and FeSOD amino acid sequences revealed that they have higher homology to, and complete conservation of, invariant residues found in iron-containing SODs. Southern blot analysis showed that one gene, L.c.FeSODA, is a single copy gene, whereas the other gene, L.c.FeSODB, belongs to a multi-gene family. Transcript levels and enzyme activities of L.c.FeSODA and L.c.FeSODB show differential stage expression, with higher levels present in the amastigote stage of the parasite compared to the promastigote stage. Expression of the L.c.FeSODs in an E. coli SOD null strain protected the bacteria against free radical generating agents. Overexpression of these FeSODs in L. chagasi parasites also showed enhanced protection against the free radical generating agents, paraquat and nitroprusside. The cloning, characterization and overexpression of the L.c.FeSODA and L.c.FeSODB genes and proteins demonstrates the possible role of SODs in Leishmania pathogenesis.

Amino Acid Sequence↗

Fluorescence in situ hybridization assessment of the telomeric regions of jumping translocations in a case of aggressive B-cell non-Hodgkin lymphoma.

We report a jumping translocation involving a donor chromosome 1 long arm in a case of aggressive B-cell non-Hodgkin lymphoma (NHL). Conventional cytogenetic banding studies demonstrated a breakpoint distal to the heterochromatic region of the donor 1q chromosome. Characterization by fluorescence in situ hybridization (FISH) of the jumping translocation demonstrated an apparent telomeric sequence loss of the recipient chromosomes. Additional cytogenetic aberrations, including the t(18;22) translocation associated with non-Hodgkin lymphoma, were also observed in this case. Cytogenetically similar cases of jumping translocations reported in the literature have implicated a preferential involvement of the donor chromosomes' heterochromatic regions and the telomeric regions of the recipient chromosomes. Jumping translocations are still considered rare and their appearance is associated with a poor prognosis. The presence of these specific findings for this case are discussed and compared with those previously reported in other hematologic disorders.

Chromosome Banding↗

Molecular cloning and characterization of two iron superoxide dismutase cDNAs from Trypanosoma cruzi.

Two cDNAs (FeSODA and FeSODB cDNAs) corresponding to superoxide dismutase (1.15.1.1., SOD) were isolated from a Trypanosoma cruzi cDNA library. Comparison of the deduced amino acid sequences with previously reported SOD protein sequences revealed that the T. cruzi open reading frames had considerable homology with FeSODs. The coding region of the T. cruzi FeSODB cDNA has been expressed in fusion with glutathione-S-transferase using an Escherichia coli mutant QC779, lacking both MnSOD and FeSOD genes (sodA sodB). Staining of native polyacrylamide gels for SOD activity of T cruzi crude lysate and the recombinant SOD suggests that this protein is an FeSOD. The recombinant enzyme also protected the E. coli mutant QC779 from paraquat toxicity. Northern blot analysis showed that FeSODB is differentially expressed, showing a higher level at the epimastigote stage of T. cruzi development; whereas, FeSODA is constitutively expressed at a lower level in all developmental stages. Furthermore, Southern hybridization shows that both FeSODA and FeSODB genes appear to be present in the T. cruzi genome as multiple repeating units (multi-copy gene family).

Amino Acid Sequence↗

[Ulnar nerve fascicle transfer onto to the biceps muscle nerve in C5-C6 or C5-C6-C7 avulsions of the brachial plexus. Eighteen cases].

The authors report 18 cases of transfer of several ulnar nerve fascicles onto the biceps muscle nerve, performed between 1990 and 1997. The patients were between the ages of 17 and 41 years, and presented C5-C6 paralysis in 8 cases and C5-C6-C7 paralysis in 10 cases. The operation was tempted between 4 months and 6 years (m = 17 months) after the initial accident. In the 8 cases of C5-C6 paralysis reviewed, 7 patients recovered elbow flexion and only one required an additional Steindler transfer. In the 9 cases of C5-C6-C7 paralysis reviewed, 4 patients recovered elbow flexion after nerve surgery alone, while 4 patients only obtained elbow flexion after a complementary Steindler transfer. Two of these 4 patients were operated very late (27 and 75 months). Finally, a single 40-year-old patient, operated 28 months after the accident, was considered to be a complete failure. Overall, ulnar biceps nerve transfer appears to be indicated in C5-C6 avulsion, during the months following the initial accident. Flexion against gravity is then regularly obtained in less than 6 months, without any objective or subjective sequelae of the hand.

Adolescent↗

Distal insertions of abductor pollicis longus muscle and arthritis of the first carpometacarpal joint in 104 dissections.

The different types of distal insertions of the tendons of the abductor pollicis longus muscle (APL) were studied in 104 cadaveric hands, and the appearance of the rhizarthrosis in the level of the basal joint of the thumb, as well, in a try to detect possible anatomical relationships. From the anatomical point of view, it was evident that the insertions of the APL muscle are usually multiple (95%), that the insertion to the base of the first metacarpal is constantly present, accompanied in 70% of the cases with an insertion to the trapezium. Finally, the accessory tendon to the thenar eminence was proved to be extremely frequent (42%). Rhizarthrosis has been found in 97% of the dissections. The lateral compartment of the joint surface appeared to be the most frequently affected with arthritis (71%) and probably the starting point of the lesion. But no correlation has been recorded between severe arthritis and any type of distal insertion of abductor pollicis longus muscle. Early tenotomy of some tendons, in order to prevent arthritis of the first CMC joint, cannot be recommended from this study.

Arthritis↗

Calcium-dependent protein kinase genes in corn roots.

Two cDNAs encoding Ca(2+)-dependent protein kinases (CDPKs), CRPK1 and CRPK2 (corn root protein kinase 1 and 2), were isolated from the root tip library of corn (Zea mays L., cv. Merit) and their nucleotide sequences were determined. Deduced amino acid sequences of both the clones have features characteristic of plant CDPKs, including all 11 conserved serine/threonine kinase subdomains, a junction domain and a calmodulin-like domain with four Ca(2+)-binding sites. Northern analysis revealed that CRPK1 mRNA is preferentially expressed in roots, especially in the root tip; whereas, the expression of CRPK2 mRNA was very low in all the tissues tested. In situ hybridization experiments revealed that CRPK1 mRNA is highly expressed in the root apex, as compared to other parts of the root. Partially purified CDPK from the root tip phosphorylates syntide-2, a common peptide substrate for plant CDPKs, and the phosphorylation was stimulated 7-fold by the addition of Ca2+. Our results show that two CDPK isoforms are expressed in corn roots and they may be involved in the Ca(2+)-dependent signal transduction process.

Amino Acid Sequence↗

Incidence and distribution of scaphotrapezotrapezoidal arthritis in 73 fresh cadaveric wrists.

The STT joint was examined in 73 fresh cadaveric specimens (25 male and 48 female with an average age of 84 years) with a view to study the incidence and characteristics of degenerative changes in this joint. The articular degeneration was graded from 0 to 3 according to increasing loss of cartilage and the location of the changes was noted. At the same time, the presence and extent of concomitant trapezio-metacarpal arthritis was noted. 61 of the 73 hands (83.3%) were found to present STT arthritis. Degeneration of the trapezoid articular surface was:- more frequent: 53 hands (72.6%) as compared to 48 (65.7%),-of greater severity: 40 cases (55%) of grades 2/3 as compared to 25 (34%), than that of the trapezium. Concomitant or isolated arthritis in the trapezometacarpal joint (90.4%) was present in 66 of the 73 hands (79%) examined with grade 3 changes in 13 cases. The apparent predominance of degeneration in the scapho trapezoidal articulation could, perhaps, lead us to assume that this might be the site of origin of STT arthritis. It could also explain the persistence of symptoms following prosthetic replacement of the trapezium.

Aged↗

Cytology. A valuable tool in prognostication of carcinoma breast.

Sixty consecutive cases of carcinoma breast diagnosed on fine needle aspiration cytology (FNAC) between July 1993 to June 1994 were studied prospectively. Nuclear grading was done on all cytologic smears, histologic grading was possible in only 22 cases. A good correlation was seen between nuclear grading on cytology and histology. Silver staining for nucleolar organizer region, and immunocytochemical staining for Ki-67 and C-erbB-2 could be done with ease on cytologic smears, providing necessary additional information on which to base the theraputic decisions.

Biopsy, Needle↗