Two doses of measles vaccine: are some states in India ready for it?

We present the results of two surveys of measles outbreaks near Vellore, which perhaps supports the cause for introduction of a second dose of measles vaccine. Survey one had 590 under 10-year olds. The attack rate was 15.1, 11.7 and 5.7% in the unimmunized, among those vaccinated at 6 months and at 9 months, respectively. The overall vaccine efficacy (VE) was 28% if vaccinated at 6 months and 66% if at 9 months. Second survey had 1702 children and adolescents. There were 59 cases of measles of which 49 were over 5 years of age, the mean age being 8.8 years. The VE was 66% for children up to 6 years and 48.4% for those aged 7-15. The data suggests that measles vaccine is better given at 9 months. The low VE in school age children could be improved by introducing a second dose of measles vaccine.     

Macroorchidism in an Indian Boy with McCune-Albright Syndrome

McCune-Albright syndrome (MAS) is defined by the clinical triad of fibrous dysplasia of bone (FD), café-au-lait spots and precocious puberty (PP). It is a rare disease with estimated prevalence between 1/100,000 and 1/1,000,000. The authors report a case of MAS in an Indian boy who had history of unilateral macroorchidism (but no other signs of MAS) since birth, then presented with PP, FD and café-au-lait spots at 6 years of age. On examination he had asymmetry of the face, café-au-lait spots and signs of sexual precocity with a right testicular volume of 25 ml (left 8 ml). Investigations revealed suppressed gonadotropins with elevated testosterone levels. Skeletal survey showed dysplastic changes involving multiple bones and advanced bone age. Reports of MAS in a boy with unilateral macroorchidism are scarce. Thus, unilateral macroorchidism at birth in a baby may be a feature of MAS and should be followed up with care.     

Malassezia furfur in a case of onychomycosis: colonizer or etiologic agent?

The etiologic role of Malassezia furfur in onychomycosis is a contentious diagnostic problem because its keratinolytic ability has never been verified. This case report describes the isolation of M. furfur from the infected nails of a child clinically diagnosed with onychomycosis, and discusses the role of this organism as an etiologic agent/colonizer. The patient presented with subungual hyperkeratosis and onycholysis without associated paronychia. Budding yeast cells compatible with M. furfur were repeatedly demonstrated in KOH wet mounts of damaged nails, histopathology of hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) stained sections showed penetration of fungal elements between deeper layers of keratin, and numerous colonies of M. furfur were isolated on three consecutive occasions from nail specimens collected from different areas of hand and toenail lesions. No evidence of nail invasion by dermatophytic or nondermatophytic filamentous fungi were found by direct microscopy or culture. Microscopy and culture were negative following 12 weeks of ketoconazole treatment, which resulted in growth of healthy nail plates with normal beds. We can infer from these observations that M.furfur was an etiologic agent rather than a colonizer in the patient's nails even though direct keratinolytic character of this fungus was not demonstrated.     

Three-dimensional fluorescence lifetime tomography

Near-infrared fluorescence tomography using molecularly targeted lifetime-sensitive, fluorescent contrast agents have applications for early-stage cancer diagnostics. Yet, although the measurement of fluorescent lifetime imaging microscopy (FLIM) is extensively used in microscopy and spectroscopy applications, demonstration of fluorescence lifetime tomography for medical imaging is limited to two-dimensional studies. Herein, the feasibility of three-dimensional fluorescence-lifetime tomography on clinically relevant phantom volumes is established, using (i) a gainmodulated intensified charge coupled device (CCD) and modulated laser diode imaging system, (ii) two fluorescent contrast agents, e.g., Indocyanine green and 3-3'-Diethylthiatricarbocyanine iodide differing in their fluorescence lifetime by 0.62 ns, and (iii) a two stage approximate extended Kalman filter reconstruction algorithm. Fluorescence measurements of phase and amplitude were acquired on the phantom surface under different target to background fluorescence absorption (70:1, 100:1) and fluorescence lifetime (1:1, 2.1:1) contrasts at target depths of 1.4-2 cm. The Bayesian tomography algorithm was employed to obtain three-dimensional images of lifetime and absorption owing to the fluorophores.     

Crosslinked chitosan: its physical properties and the effects of matrix stiffness on chondrocyte cell morphology and proliferation

Chitosan [beta(1-4)-2 amino-2-deoxy-D-glucose], the natural polyaminosaccharide derived from N-deacetylation of chitin [beta(1-4)-2 acetamide-2-deoxy-D-glucose], has been shown to possess attractive biological and cell interactive properties. Recently chitosan and chitosan analogs have also been shown to support the growth and continued function of chondrocytes. In the present study, chitosan substrates are crosslinked with a functional diepoxide (1,4 butanediol diglycidyl ether) to alter its mechanical property, and the viability and proliferation of the canine articular chondrocytes seeded on the crosslinked surface are further assayed. Of interest is the impact of substrate stiffness on the growth and proliferation of articular canine chondrocytes. Crosslinked scaffolds were also subjected to degradation by chitosanase to examine the impact of crosslinking on enzyme-assisted degradation. The hydrophilicity and compression modulus of the crosslinked surfaces were measured via contact-angle measurements and compression tests, respectively. Scanning electron microscopy (SEM) and fluorescent staining were used to observe the proliferation and morphology of chondrocyte cells on noncrosslinked and crosslinked surfaces. The crosslinked chitosan was found to be nontoxic to chondrocytes and more hydrophilic. Its compression modulus and stiffness increased, which may improve the scaffold resistance to wear and in vivo shrinkage once implanted. The increased stiffness also seemed to serve as an additional mechanical stimulus to promote chondrocyte growth and proliferation. The cell morphology on crosslinked scaffolds seen by SEM and fluorescent stain was the typical chondrocytic rounded shape. The method proposed provides a nontoxic way to increase the mechanical strength of the chitosan scaffolds.     

Response of bone subjected to optimized high dose irradiation

Allograft tissues are used in over one million musculoskeletal procedures per year. Consequently, it is crucial tissue banks use procedures to militate against allograft associated bacterial and viral infections. Recent studies have identified an important pathogen inactivation technology for musculoskeletal allografts that utilizes high-dose gamma irradiation (50 kGy) under controlled conditions. A total dose of 50 kGy assures that the current standard for medical devices for a microbial sterility assurance level of 10(- 6) is met. Furthermore, the pathogen inactivation technology results in a greater than four log inactivation of enveloped and nonenveloped viruses. Efficacious clinical outcome from musculoskeletal allografts exposed to this innovative sterilization procedure will require that there is no performance decrement in the allograft's biological properties. Therefore, to validate this objective, we executed a study focusing on remodeling and osteoconduction of bone allografts treated with a high dose of gamma irradiation (50 kGy), radioprotectants and well-defined operating parameters of temperature and water content. A rabbit calvarial model was used to test the hypothesis that remodeling and osteoconduction of allogeneic bone treated with the new pathogen inactivation technology would be equivalent to nontreated allogeneic bone. Results indicated treated bone allografts were comparable to nontreated allografts. We conclude, therefore, that based on this outcome and other reports, that high doses of gamma irradiation under optimized conditions designed to reduce free radical damage to tissue will provide safer allografts.     

Deficient SOCS3 expression in CD4+CD25+FoxP3+ regulatory T cells and SOCS3-mediated suppression of Treg function

Naturally occurring CD4+CD25+FoxP3+ regulatory T cells (Treg) suppress T helper (Th) cell-mediated immune responses. The cytokines IL-2 and IL-6 are known to influence Treg function. However, their relative effects on Th cells versus Treg are not well understood. Stimulation with IL-2, and to a lesser extent, IL-6, enhanced Treg proliferation, FoxP3 and CTLA4 maintenance, and suppressive function. In contrast, when IL-2 or IL-6 were added to Treg/Th cell cocultures, suppression was inhibited. The molecule SOCS3 negatively regulates responses to IL-2 and IL-6. Interestingly, unlike Th cells, Treg were found to be deficient in SOCS3 protein expression. The significance of this finding lies in the need for Treg to rapidly respond to these cytokines to prevent unwarranted immune responses to self-antigens. Overexpression of SOCS3 in Treg decreased their proliferation, FoxP3 and CTLA-4 expression and suppressive function. Thus, up-regulation of SOCS3 expression may be a useful therapeutic approach in diseases where inhibition of Treg is desirable.     

Comparison of ethylenediaminetetraacetic acid and sodium citrate as anticoagulants in collection of samples for cytomegalovirus pp65 antigen detection in renal transplant recipients with suspected cytomegalovirus disease

Cytomegalovirus (CMV) is a major cause of morbidity and mortality in immunocompromised patients. Antigenemia and polymerase chain reaction (PCR) assay are used for diagnosis of CMV disease. A number of anticoagulants are used for the collection of blood samples for antigenemia assay. Thus, ethylenediaminetetraacetic acid (EDTA) and sodium citrate are evaluated for the collection of blood samples and their effects on antigenemia and PCR. Twenty renal transplant recipients with clinically suspected CMV disease and 10 healthy individuals were included in the study. Peripheral blood mononuclear cells (PBMCs) extracted from blood samples were subjected for antigenemia and PCR assay. In 15 out of 20 patients, the number of peripheral blood mononuclear cells obtained were higher in EDTA anticoagulated samples than in sodium citrate. CMV pp65 antigenemia was detected in 10 EDTA and 9 sodium citrate samples, respectively. Number of antigen positive cells in EDTA samples were significantly higher than that of sodium citrate (P<0.05). None of the anticoagulants had adverse effect on the detection of CMV DNA. Thus, EDTA was found to be a better anticoagulant for separation of PBMCs and thus, for CMV pp65 antigenemia assay than sodium citrate.     

Association of novel variants in the hepatocyte nuclear factor 4A gene with maturity onset diabetes of the young and early onset type 2 diabetes

Variants in hepatocyte nuclear factor 4A (HNF4A) cause maturity onset diabetes of the young (MODY 1). The objective of the study was to screen the coding and the promoter regions of HNF4A mutations in 87 unrelated South Indian subjects with clinically diagnosed MODY with severe forms of diabetes referred to a tertiary diabetes centre. In addition, we looked at the association of common polymorphisms in HNF4 A gene in subjects with MODY (n = 199), early onset type 2 diabetes (T2DM) (n = 505), late onset T2DM (n = 287) and normal glucose tolerance (NGT) (n = 247). We identified three novel mutations in the P2 promoter region of HNF4A, namely -1009 G/C, -129 T/C and -79 C/T. Co-segregation with diabetes was noted with the -1009 G/C and -129 T/C in one MODY family. We also studied eight single nucleotide polymorphisms (SNPs) of HNF4A gene. The frequency of the minor allele of the rs2144908 was significantly higher in subjects with MODY (p < 0.01) and that of rs736823 was significantly higher in early onset T2DM (p = 0.001). Minor allele frequency of rs1884614 and rs2071197 was significantly lower in early onset T2DM when compared to NGT subjects (p < 0.01). Minor allele frequency of Val255Met was significantly lower in MODY, early onset T2DM and late onset T2DM compared to NGT subjects (p < 0.01). This is the first report of MODY 1 mutations from India and shows that 3.4% of clinically diagnosed MODY subjects have MODY 1. In addition, we report SNPs of HNF4A that are both susceptible to, and protective against, MODY and early onset T2DM.