Preparation of the hypoxia imaging PET tracer [18F]FAZA: reaction parameters and automation

18F-labeling of the nitroimidazole nucleoside analogue 1-(5-fluoro-5-deoxy-alpha-D-arabinofuranosyl)-2-nitroimidazole (FAZA) was developed to use this tracer in PET for detection of hypoxia. Parameters for labeling and hydrolysis were optimized with regard to amount of precursor, temperature and time. Labeling yields reached a maximum of 62+/-4% at 100 degrees C within 5 min using 5 mg of precursor. Hydrolysis was best performed with 1 mL of 0.1 N NaOH at 20 degrees C for 2 min. Transfer of these conditions to an automated synthesizer resulted in an overall radiochemical yield of 20.7+/-3.5%. Absolute yields at EOS were 9.8+/-2.3 GBq of [18F]FAZA ready for injection (n=21; 50 min after EOB; irradiation parameters: 35 microA, 60 min). Thus, a convenient approach suitable for large-scale production of [18F]FAZA was developed by an automated process.

Emphysematous pyelonephritis: a consequence of adenocarcinoma of urinary bladder in a nondiabetic patient

Emphysematous pyelonephritis (EP) is a life threatening condition of acute necrotising renal parenchymal infection that encompasses a much wider spectrum of complicated urinary tract infections such as renal abscesses, emphysematous pyelitis, pyelonephritis, acute renal papillary necrosis, and sepsis. We report an unusual case of adenocarcinoma bladder in a middle aged nondiabetic patient, presenting with EP. Emphysematous pyelonephritis was the initial symptom in this case with an underlying carcinoma of the bladder. The role of imaging is prime in management of such cases, if an early diagnosis is to be made and a potentially devastating outcome is to be avoided. The literature regarding EP has been reviewed and discussed. The goals of managing EP should be (1) early institution of parenteral antibiotics and a (2) a staged nephrectomy (preceded by a temporary percutaneous drainage particularly with antibiotic resistant septicemia) so as to maximize survival rather than proceeding directly to emergency nephrectomy.

Spectrum and antibiotic susceptibility pattern of bacterial isolates from conjunctival swabs

Conjunctivitis is the most common disease of conjunctiva which occurs by exogenous or endogenous source. Bacterial conjunctivitis is the most common type of this infection for which emperical treatment is started without knowing the etiological agents because prior cultures are generally not taken. We conducted this survey to study the etiological agents of conjunctivitis in a total of 6763 swabs obtained over a period of four years (2001 to 2004). The prevalence of bacterial conjunctivitis was found to be 20.4% with a predominance of Staphylococcus aureus (87.2%) followed by Streptococcus pneumoniae (4.7%) and gram negative rods (E.coli + Klebsiella spp. + Pseudomonas spp.) in 8.1% swabs. For S. aureus, amikacin showed maximum sensitivity (73.2%) while for S. pneumoniae, cefotaxime (90.6%) and cefazolin (89%) were found to be highly sensitive drugs. For gram negative rods, ceftazidime (74.1%) and cefotaxime (67%) were found to be preferred options. Thus it is concluded that bacterial conjunctivitis in our hospital is predominated by S. aureus. The bacterial isolates obtained from conjunctiva have not yet attained a high level of antibiotic resistance and hence averts the need to unnecessarily start new/latest generations of antibiotic eyedrops or antibiotic combination which may lead to acquisition of resistance by these bacteria.

Smear morphology of cryptococcosis presenting as a subcutaneous swelling in healthy adults: a report of three cases

OBJECTIVE

To highlight the various morphological smear pattern in cases of subcutaneous Cryptococcus infection in healthy adults.

METHOD

Cryptococcus is an opportunist fungus and primary infection is acquired through respiratory tract. Dissemination by blood stream results in systemic infection. Ten to 15% of systemic infection present as cutaneous lesions. Between December 2002 and April 2004 three healthy adults presented to us consecutively with subcutaneous swelling.

RESULTS

We diagnosed these cases on FNAC as Cryptococcus. In all the three patients there was no history of local penetrating injury and any signs or symptoms of systemic disease. They were two male and one female, immuno competent and were negative for HIV 1 & 2 tested by ELISA. The sites were right abdominal flank, occipital and left anterior upper thigh. Aspirated materials were oily fibro fatty tissue and necrotic purulent materials. Cryptococcus numbers varied in all the smears so also their size and capsule thickness. Background smear morphology and tissue reaction were also different. It could be gelatinous, granulomatous, and cellulitic response or mixed responses and this can be picked up on cytological smears. Cultures were confirmatory in all the three cases. These lesions were resolved with antifungal treatment.

CONCLUSION

Our brief article highlights the morphological spectrum on FNAC smears and diagnostic problems faced in these uncommon circumstances where the aspirates were purulent and the yeasts were small, few and thin walled. In the acute inflammatory smear with occasional giant cells and/or granulomas special stains like PAS or Mucicarmine are necessary to look for budding yeast of Cryptococcus with thin neck.

An unexpectedly rapid decline in the X-ray afterglow emission of long γ-ray bursts

'Long' gamma-ray bursts (GRBs) are commonly accepted to originate in the explosion of particularly massive stars, which give rise to highly relativistic jets. Inhomogeneities in the expanding flow result in internal shock waves that are believed to produce the gamma-rays we see. As the jet travels further outward into the surrounding circumstellar medium, 'external' shocks create the afterglow emission seen in the X-ray, optical and radio bands. Here we report observations of the early phases of the X-ray emission of five GRBs. Their X-ray light curves are characterised by a surprisingly rapid fall-off for the first few hundred seconds, followed by a less rapid decline lasting several hours. This steep decline, together with detailed spectral properties of two particular bursts, shows that violent shock interactions take place in the early jet outflows.

Caudal Additives in Pediatrics: A Comparison Among Midazolam, Ketamine, and Neostigmine Coadministered with Bupivacaine

Single-shot "kiddie caudal" with bupivacaine alone is losing popularity because of its duration of 4-8 h. In a prospective randomized double-blind clinical study, we assessed and compared the efficacy of ketamine, midazolam, and neostigmine coadministered with bupivacaine in a caudal epidural to provide intraoperative and postoperative pain relief. Eighty children (ASA status I) aged 5-10 yr undergoing unilateral inguinal herniotomy were allocated randomly in equal numbers (n = 20) into 4 groups to receive a caudal injection of 0.25% bupivacaine (1 mL/kg) with or without ketamine (0.5 mg/kg), midazolam (50 microg/kg), and neostig-mine (2 microg/kg), after the induction of standardized general anesthesia without premedication. Monitoring for pain, sedation, postoperative nausea/vomiting, dizziness, and pruritus was performed by anesthesiologists blinded to the study allocation. The time to first analgesic administration (paracetamol syrup) was longer (P < 0.05) in the bupivacaine-neostigmine group and the bupivacaine-midazolam group than in the other groups. Undesirable effects, such as emesis, pruritus, and dizziness, were comparable in all groups. However, the incidence of hallucination was more frequent in the bupivacaine-ketamine group compared with the other groups. This study shows that single-shot caudal coadministration of bupivacaine-neostigmine and bupivacaine-midazolam was associated with an extended duration of postoperative pain relief.

Variability of milk fat globule membrane protein gene between cattle and riverine buffalo

A study on butyrophilin (BTN) gene was conducted to detect variability at nucleotide level between cattle and buffalo. Hae III PCR-RFLP was carried out in crossbred cattle and it revealed polymorphism at this locus. Three genotypes namely, AA, BB and AB and two alleles were observed with frequencies 0.78, 0.17, 0.04 and 0.87, 0.13, respectively. The sequences of different cattle, buffalo and sheep breeds have been reported in the EMBL gene bank with accession numbers: AY491468 to AY491475. The nucleotides, which have been substituted from allele A to B, were found to be C to G (71st nucleotide), C to T (86th nucleotide), A to T (217th nucleotide), G to A (258th nucleotide), A to C (371st nucleotide) and C to T (377th nucleotide). The nucleotide substitution at 71st, 86th and 377th position of the fragment were expected to be a silent mutation where as nucleotide changes at 217th, 258th and 371st positions were expected to be substituted by lysine with arginine, valine with isoleucine and leucine with proline in allele B. The differences of nucleotides and amino acids between cattle, buffalo and sheep breeds have been revealed and on the basis of nucleotide as well as protein variability the phylogenetic diagram have been developed indicating closeness between cattle and buffalo.

Histology, Immunohistochemistry and Ultrastructure of the Equine Palatine Tonsil

The palatine tonsils of five young horses formed 10-12 cm elongated follicular structures extending from the root of the tongue on either side to the base of the epiglottis and lateral to the glossoepiglottic fold. The stratified squamous non-keratinized epithelium of the outer surface was modified into crypts as reticular epithelium by heavy infiltration of lymphoid cells from underlying lymphoid follicles. In places, lymphoid tissue reaching almost to the surface and with only one to two cell layers intact was identified as the lymphoepithelium. Langerhans cells with Birbeck granules were interspersed between epithelial cells. Lymphoid tissue organized in lymphoid follicles constituted the parenchyma of the palatine tonsil. CD4-positive cells were more numerous and CD8-positive lymphocytes less numerous compared with their distribution in the lingual tonsil. B cells and macrophages were also more numerous than in the lingual tonsil and lectins showed a different pattern of attachment. M cells were not observed. High endothelial venules with well-developed vesiculo-vacuolar organelle had structural evidence of transendothelial and interendothelial migration of lymphocytes. Striated muscles as seen in the deeper lamina propria mucosae of the lingual tonsil were absent. The immunohistological and ultrastructural characteristics of the equine palatine tonsil are similar to those of humans but differ from those of the lingual tonsil and are consistent with a role as an effector and inductor immunological organ.

Histology, Immunohistochemistry and Ultrastructure of the Equine Tubal Tonsil

The tubal tonsil of the horse surrounds the pharyngeal opening of the eustachian tube and is lined by pseudostratified columnar ciliated epithelium interspersed with areas of follicle-associated epithelium (FAE) heavily infiltrated by lymphocytes but devoid of goblet and ciliated cells. Scanning and transmission electron microscopy revealed microvillous cells and cells with features characteristic of M cells such as reduced microvilli or depressed bare surface, more numerous mitochondria, small vesicles and lysosomes, as well as vimentin filaments and epitopes specific for GS 1-B4 as previously seen in the nasopharyngeal tonsil. M cells were also identified in areas of respiratory epithelium not associated with lymphoid follicles and appeared to be the nasal mucosal counterparts of recently described intestinal villous M cells in the mouse. The underlying lymphoid tissue of the FAE was generally organized as solitary lymphoid follicles without germinal centres in contrast to the diffuse and large amount of organized lymphoid follicles with germinal centres that characterize the nasopharyngeal tonsil. CD8+ T and B-lymphocytes were much fewer than in the nasopharyngeal tonsil. High endothelial venules were mainly oriented towards the parafollicular area and contained much fewer endothelial pores and vesiculo-vacuolar organelles. Finally, scattered small clusters of mucus acini and striated muscles were other features that differentiated the tubal and nasopharyngeal tonsils.

Annual risk of tuberculous infection in four defined zones of India: a comparative picture

SETTING

Twenty-six selected districts in India.

OBJECTIVES

To estimate the average annual risk of tuberculous infection (ARTI) in four defined zones in the country.

STUDY DESIGN

A tuberculin survey was conducted in selected clusters of 26 districts in four defined zones of India. Children 1-9 years of age were subjected to tuberculin testing with ITU PPD RT23 with Tween 80, and the maximum transverse diameter of induration was measured 72 h later. Prevalence of infection was estimated using the cut-off point method (Method I) and the mirror-image technique (Method II) among children without bacille Calmette-Guérin scar. Results from individual zones have been reported earlier, and the results from all four zones are presented here as a consolidated summary.

RESULTS

The ARTI computed from estimated prevalence was found to be lowest in the southern zone (Method I: 1.1%, Method II: 1.0%). It was higher in the eastern zone (1.3% by both methods) and highest in the western (Method I: 1.8%, Method II: 1.6%) and northern zones (1.9% by both methods). The proportion of infected children was found to be significantly higher in urban than in rural areas in all zones.

CONCLUSION

The intensified tuberculosis control efforts need to be sustained for many years.

Gene activation and protein expression following ischaemic stroke: strategies towards neuroprotection

Current understanding of the patho-physiological events that follow acute ischaemic stroke suggests that treatment regimens could be improved by manipulation of gene transcription and protein activation, especially in the penumbra region adjacent to the infarct. An immediate reduction in excitotoxicity in response to hypoxia, as well as the subsequent inflammatory response, and beneficial control of reperfusion via collateral revascularization near the ischaemic border, together with greater control over apoptotic cell death, could improve neuronal survival and ultimately patient recovery. Highly significant differences in gene activation between animal models for stroke by middle cerebral artery occlusion, and stroke in patients, may explain why current treatment strategies based on animal models of stroke often fail. We have highlighted the complexities of cellular regulation and demonstrated a requirement for detailed studies examining cell specific protective mechanisms after stroke in humans.

Histology and Ultrastructure of the Equine Lingual Tonsil. II. Lymphoid Tissue and Associated High Endothelial Venules

The stratified squamous epithelium of the lingual tonsil of five young horses was infiltrated with CD4 and CD8 positive cells, which were very numerous in the crypt reticular epithelium along with macrophages and IgGb and IgA positive cells. Lymphoid follicles of the lamina propria mucosae consisted of a parafollicular area, corona and germinal centre. The parafollicular area was populated by large numbers of CD4 and CD8 positive lymphocytes as well as macrophages, inter-digitating cells, and a few B-lymphocytes. The germinal centre contained mainly IgGb and IgG(T) positive cells, plasma cells and small numbers of follicular dendritic cells, macrophages, CD4, CD8 and IgA positive cells. Some venules in the parafollicular and inter-follicular areas had features characteristic of high endothelial venules with irregular nuclei and cytoplasmic processes on the luminal surface. In addition to the normal cytoplasmic organelles, a novel vesiculo-vacuolar organelle was observed in small clusters toward the lateral, luminal and abluminal surfaces of these high endothelial venules. These vesiculo organelles along with their stomata and diaphragms, communicated with each other and with inter-endothelial clefts forming a structural basis for enhanced permeability and extravasation of macromolecules. The presence of lymphocytes in the high endothelial venules is consistent with transmural and inter-endothelial passage of these cells.

The prevalence of pressure ulcers in hospitalised patients in a university hospital in India

OBJECTIVE

To estimate the prevalence of pressure ulcers in hospitalised patients and any underlying or predisposing factors to ulceration.

METHOD

This cross-sectional study took place in a university hospital in Varanasi, India. A total of 445 patients hospitalised in medical and surgical wards were examined in a single day for the number, site and grade of pressure ulcers. Haemoglobin, serum albumin and blood sugar levels of patients with pressure ulcers were recorded.

RESULTS

The prevalence of pressure ulcers was high (4.94%). Anaemia, malnutrition and diabetes were important risk factors, while morbidity due to pressure ulcers in long-stay wards, such as neurology, was exceptionally high (40.9%).

CONCLUSION

Pressure ulcers remain one of the most neglected aspects of health-care provision in India and identifying their associated risk factors at an early stage may go a long way in preventing their occurrence.