Head and Neck Histoplasmosis—A Nightmare for Clinicians and Pathologists! Experience at a Tertiary Referral Cancer Centre

Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed. All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended. This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON 2006.     

Characterization of solid-state forms of celecoxib.

This study deals with the generation and characterization of various solid-state forms of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor. The drug was subjected to polymorphic screen using different solvents to explore the possibility of existence of different solid forms. N,N-Dimethyl acetamide (DMA) and N,N-dimethyl formamide (DMF) yielded solvates in 1:1 stoichiometric ratio. Quench cooling of the melt resulted in amorphous form of the drug. All these solid-state forms were characterized by thermoanalytical (DSC, TGA, HSM), crystallographic (XRD), microscopic (polarized, SEM), spectroscopic (FTIR), and elemental analysis techniques. Solubility and van't Hoff studies were carried out for their thermodynamic interpretation. Influence of morphology of different solid-state forms on flow behavior was also investigated. Molecular modeling studies were used to elucidate the interaction between solute and solvent molecules in the solvate.     

Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk

Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.     

Emergency department visits for asthma: the role of frequent symptoms and delay in care.

BACKGROUND: Use of the emergency department (ED) for asthma care is a costly form of health care that is largely preventable. However, little is known about how to reduce the number of people using the ED for asthma care. OBJECTIVE: To identify modifiable factors related to ED visits for asthma among a diverse nonelderly adult population. METHODS: This study used cross-sectional data from the 2001 California Health Interview Survey. A total of 4,359 adult respondents ages 18 to 64 years who reported being diagnosed as having asthma and experiencing symptoms in the past year were included. Any ED visits due to asthma in the previous 12 months among all nonelderly respondents with asthma, with stratification by those with daily or weekly symptoms and with less frequent symptoms, were examined. RESULTS: Adults with daily or weekly asthma symptoms, with fair or poor health status, and who delayed care for asthma because of cost or insurance issues were more likely to visit the ED for asthma. Stratification of the study population into those with daily or weekly symptoms and those with less frequent symptoms revealed that delay in care due to cost or insurance issues and fair or poor health status remained significant for both groups. Latinos and women were more likely to visit the ED in the severe asthma group, whereas Asian, African American, and uninsured adults were more likely to visit the ED in the group with less severe asthma. CONCLUSIONS: Results suggest that to prevent ED visits for asthma, it is important to control asthma symptoms. However, it is equally if not more important to reduce delays in receiving asthma care.     

Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system

Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.      

Detection of chromosomes and estimation of aneuploidy in human spermatozoa using fluorescence in-situ hybridization

The development and application of fluorescence in-situ hybridization (FISH) has opened the way for comprehensive studies on numerical chromosome abnormalities in human spermatozoa. FISH can be rapidly applied to large numbers of spermatozoa and thus overcomes the major limitation of karyotyping spermatozoa after penetration of zona-free hamster oocytes. The simultaneous hybridization of two or more chromosome-specific probes to spermatozoa and subsequent detection of the bound probes using different fluorescent detection systems enables two or more chromosomes to be localized simultaneously in the same spermatozoon and provides a technique for undertaking reasonable estimates of aneuploidy. The most commonly used probes are those which bind to the centromeric region of specific chromosomes. Most studies to date have concentrated on estimating aneuploidy in spermatozoa from normospermic men, although reports are beginning to appear on aneuploidy in spermatozoa from subfertile and infertile men. Multi- probe FISH studies have generally reported disomy (hyperhaploidy) estimates of 0.05-0.2% per chromosome. There is preliminary evidence that some chromosomes such as X, Y and 21 are predisposed towards higher rates of non-disjunction during spermatogenesis. There are also suggestions of inter-donor variability in aneuploidy frequencies for specific chromosomes, although this requires confirmation in larger studies. While FISH is clearly a powerful technique that has many applications in reproductive medicine, it must also be realized that it does have limitations and the technology itself is still evolving and has yet to be fully validated on spermatozoa.      

Identification of semen in 500 patients seen because of rape

Of 500 patients seen because of rape, semen was identified in vaginal secretions by the identification of spermatozoa in 61%, by an acid phosphatase value of 50 units or more in 40%, and by the identification of a foreign blood group substance or a high titer of own blood group substance in 16%. The addition of the determination of the acid phosphatase to the search for spermatozoa identified semen in only 1.4% more patients, or a total of 62.4%. Identification and titers of blood group substance were confirmatory only, but further characterized the source of the semen in 25% of those patients with spermatozoa. Spermatozoa were identified for as long as 48 hours, and elevated acid phosphatase was not found after 18 hours. Acid phosphatase was elevated in only 62% of patients with spermatozoa.     

Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography

In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos arose from oocytes that had more uniform timing from injection to pronuclear abuttal and tended to have a longer cytoplasmic wave. In conclusion, we have shown that time-lapse video cinematography is an excellent tool for studying fertilization and early embryo development, and have demonstrated that human fertilization comprises numerous complex dynamic events.      

Persistent tubular conduction in vacuolated amphibian skeletal muscle following osmotic shock

The transverse (T-)tubules primarily function in conducting the action potentials that initiate excitation– contraction coupling in skeletal muscle but may additionally subserve longer-term roles in volume regulation, membrane fusion and other trafficking processes. Osmotic shock thus both electrically detaches the T-tubules from surface membrane (‘detubulation’) and produces tubular vacuolation. The present experiments separated these effects. An established, reference osmotic shock protocol that exposed muscles to Ca²⁺/Mg²⁺-Ringer and gradual cooling to 10°C after 18 min in glycerol–Ringer accomplished significant detubulation (77.5 ± 13.15%, mean ± SEM; n = 4). In contrast, a test protocol conducted entirely at room temperature using Mg²⁺-rather than Ca²⁺/Mg²⁺-Ringer yielded reduced (P < 0.05, post hoc Duncan's multiple range test) detubulation indices (1.67 ± 1.67%, n = 6) statistically indistinguishable from findings in fibres spared osmotic shock. Yet both osmotic shocks caused a formation of closed vacuoles, demonstrated by Sulphorhodamine B trapping, that occupied statistically similar fractions of total fibre volume (reference procedure: 14.38 ± 2.7%, n = 6; test procedure: 13.36 ± 2.00%, n = 22) in turn higher than determinations in control fibres (P < 0.05). The findings reconcile reports associating detubulation with vacuolation in osmotically shocked muscle [S. Nik-Zainal et al. (1999) J Muscle Res Cell Motil 20: 45–53; K.N. Khan et al. (2000) J Muscle Res Cell Motil 21: 79–90] with the persistence of tubular electrical activity in extensively vacuolated amphibian fibres following fatigue [J. Lannergren and H. Westerblad (1987) Acta Physiol Scand 129: 311–318; J. Lannergren et al. (1999) J Muscle Res Cell Motil 20: 19–32]. Furthermore test protocols produced higher densities of open vacuoles (13.38 ± 2.33%, n = 9) than did reference protocols (6.66 ± 1.63%, n = 20) contrary to their possible involvement in the electrophysiological changes. Abolition of tubular electrophysiological activity thus either follows or is independent of tubular vacuolation whilst sharing some of its underlying osmotic mechanisms. This revised version was published online in July 2006 with corrections to the Cover Date.     

Melanotropic activity in extrahypophyseal regions of rodent brain: effect of age, hormones, and drugs.

Two or more melanotropic peptides are present in extrahypophyseal regions of mammalian brain. Previous studies showed that extrahypophyseal melanotropic activity is not influenced by hypophysectomy, adrenalectomy, or exogenous glucocorticoid. The present study investigated the possible influence of the following factors on the level of melanotropic activity in whole brain, cerebral cortex, cerebellum, midbrain, and brainstem of mouse and rat: age, sex, starvation; and of the following hormones or drugs administered by the intraperitoneal or intracerebral route: norepinephrine, dihydroxyphenylalanine, pargyline, 6-hydroxy-dopamine, alpha-methyltyrosine methyl ester, reserpine, acetylcholine, pilocarpine, atropine, serotonin, p-chlorophenylalanine, pentobarbital, pentylenetetrazol, insulin, melatonin, and cycloheximide. Only age influenced extrahypophyseal melanotropic activity. The activity per unit of tissue wet weight or of tissue protein increased in all regions progressively from birth to 1 yr of age. Extrahypophyseal melanotropic activities perunit wet weight of tissue at 50 wk averaged 4.3 times those at birth. When brain of adult rodents was fractionated by differential centrifugation, the major proportion of melanotropic activity was recovered in myelin (27-35 percent), nerve endings (20-22 percent), and mitochondria (25-30 percent). The lower activity in newborn brain resulted not onlyfrom absence of a myelin fraction, but also from lower activity at birth in nerve endings and mitochondria.