Bystander activation involving T lymphocytes in herpetic stromal keratitis

Herpes simplex virus infection of mouse corneas can lead to the development of an immunopathological lesion, termed herpetic stromal keratitis (HSK). Such lesions also occur in TCR-transgenic mice backcrossed to SCID (TgSCID) that are unable to mount detectable HSV-specific immune responses. The present study demonstrates that lesion expression in such mice depends on continuous viral replication, whereas in immunocompetent mice, lesions occurred even if virus replication was terminated at 4 days after infection. The continuous replication in TgSCID mice was considered necessary to produce an activating stimulus to CD4(+) T cells that invade the cornea. Lesions in TgSCID were resistant to control by cyclosporin A, but were inhibited by treatment with rapamycin. This result was interpreted to indicate that T cell activation involved a non-TCR-mediated cytokine-driven bystander mechanism. Bystander activation was also shown to play a role in HSK lesions in immunocompetent mice. Accordingly, in immunocompetent DO11.10 mice, lesions were dominated by KJ1.26(+) OVA-specific CD4(+) T cells that were unreactive with HSV. In addition, KJ1.26(+) HSV nonimmune cells parked in ocularly infected BALB/c mice were demonstrable in HSK lesions. These results provide insight for the choice of new strategies to manage HSK, an important cause of human blindness.

Hypoglycemia associated with clonidine testing for growth hormone deficiency

We have observed 4 cases of hypoglycemia associated with clonidine stimulation of growth hormone secretion; only one patient had growth hormone deficiency. Significant drowsiness after administration of clonidine may prolong the period of fasting in these children and mask early signs and symptoms, leading to severe hypoglycemia.

Validity of an ELISA for N-acetyltransferase-2 (NAT2) phenotyping

A competitive antigen ELISA was previously developed for NAT2 phenotyping, using caffeine as the probe drug. The ELISA phenotypes by measuring the ratio of 5-acetamido-6-amino-3-methyluracil (AAMU) and 1-methylxanthine (1X) after transformation of 5-acetamido-6-formylamino-3-methyluracil (AFMU) to AAMU, in contrast to capillary electrophoresis high-pressure liquid chromatography (HPLC) which phenotype by measuring the AFMU/1X ratio. The ELISA phenotyping was previously determined in 30 samples and correlated well with phenotypes determined by capillary electrophoresis (29/30). The correlation was extended with the standard HPLC methodology by expanding the data set by 146 in order to test the validity of the ELISA methodology. The correlation with HPLC in this larger sample size was 96%; whereas the correlation between the two methods for determination of 1X was high (r(2)=0.90), that for determination of AAMU by ELISA and AFMU by HPLC was low (r(2)=0.53). The poor correlation between the two methodologies could not be attributed to the age of urine samples, nor to a significant decomposition of AFMU in the body prior to collection of the urine sample. The addition of a simple caffeine metabolite extraction method, originally developed for HPLC analysis of metabolites, to the ELISA phenotyping protocol produced a methodology with absolute correlation to the standard HPLC method.

Recurrent eclampsia in a woman with chronic pyelonephritis

Pre-eclampsia associated with chronic pyelonephritis is not uncommon, but recurrent eclampsia in two successive pregnancies associated with chronic pyelonephritis is very rare. We present one such rare case where a patient had recurrent eclampsia with chronic pyelonephritis.

Impact of a multimedia breast cancer education intervention on use of mammography by low-income Latinas

BACKGROUND

This paper describes the results of a study of a multimedia breast cancer educational intervention for low-education, low-income Latinas.

METHODS

Study participants were first exposed to an interactive, multimedia breast cancer educational intervention and then interviewed four months later to ascertain their mammography status.

RESULTS

About 40% of the women who had either obtained or scheduled mammography since the intervention attributed their decision to the intervention.

CONCLUSION

Women who had previously been screened and who understood that mammography was used as a breast cancer screening method were more likely to have scheduled or obtained mammography than other women.

Oxygen free radical injury is sufficient to cause some Alzheimer-type molecular abnormalities in human CNS neuronal cells

Cell loss and neuritic/cytoskeletal lesions represent two of the major categories of dementia-associated structural abnormalities in Alzheimer's disease (AD). Cell loss is ultimately mediated by apoptosis and mitochondrial DNA damage due to enhanced sensitivity to oxidative stress, but the mechanism responsible for the neuritic/cytoskeletal lesions including the abnormal proliferation of cortical neurites is not known. This study examines the potential role of oxygen free radical injury as a factor contributing to both cell death and neuritic sprouting cascades in AD. PNET2 human neuronal cells were treated with H2O2 (8 micro M to 88 micro M) for 24 hours and then analyzed for viability, DNA damage, and pro-apoptosis, survival, and sprouting gene expression and signaling. H2O2-treatment resulted in dose-dependent increases in cell death due to genomic and mitochondrial DNA damage associated with increased levels of 8-OHdG and the p53 and CD95 pro-apoptosis genes, reduced levels of the Bcl-2 survival gene, activation of JNK and p38 stress kinases, and inhibition of PI3 kinase survival signaling. However, the H2O2-treated cells also manifested increased expression of growth and sprouting molecules, including GAP-43, nitric oxide synthase 3, neuronal thread protein (NTP; approximately 17 kD and approximately 21 kD forms), proliferating cell nuclear antigen, and phospho-Erk MAPK, and normal levels of the AD-associated approximately 41 kD NTP species, cyclin dependent kinase 5 (cdk-5), and phospho-tau. In addition, the H2O2-treated cells had increased levels of p25, the catalytically active and stable cleavage product of p35, which regulates cdk-5 activity. Previous studies demonstrated p25 accumulation in AD brains and p25-induced hyperphosphorylation of tau and neuronal apoptosis. The findings herein suggest that oxygen free radical injury in human CNS neuronal cells is sufficient to cause some but not all of the pro-death and pro-sprouting molecular abnormalities that occur in AD.

Partial rescue of ethanol-induced neuronal apoptosis by growth factor activation of phosphoinositol-3-kinase

BACKGROUND

Ethanol inhibition of insulin signaling pathways may contribute to impaired central nervous system (CNS) development in the fetal alcohol syndrome and brain atrophy associated with alcoholic neurodegeneration. Previous studies demonstrated ethanol inhibition of insulin-stimulated growth in PNET2 CNS-derived proliferative (immature) neuronal cells. We now provide evidence that the growth-inhibitory effect of ethanol in insulin-stimulated PNET2 cells is partly due to apoptosis.

METHODS

Control and ethanol-treated PNET2 cells were stimulated with insulin and analyzed for viability, apoptosis, activation of pro-apoptosis and survival gene expression and signaling pathways, and evidence of caspase activation.

RESULTS

Ethanol-treated PNET2 neuronal cells exhibited increased apoptosis mediated by increased levels of p53 and phospho-amino-terminal c-jun kinase (phospho-JNK), and reduced levels of Bcl-2, phosphoinositol 3-kinase (PI3 K), and intact (approximately 116 kD) poly (ADP ribose) polymerase (PARP), a deoxyribonucleic acid repair enzyme and important substrate for caspase 3. Partial rescue from ethanol-induced neuronal cell death was effected by culturing the cells in medium that contained 2% fetal calf serum instead of insulin, or insulin plus either insulin-like growth factor type 1 or nerve growth factor. The resulting enhanced viability was associated with reduced levels of p53 and phospho-JNK and increased levels of PI3 K and intact PARP.

CONCLUSIONS

The findings suggest that ethanol-induced apoptosis of insulin-stimulated neuronal cells can be reduced by activating PI3 K and inhibiting pro-apoptosis gene expression and intracellular signaling through non-insulin-dependent pathways.

Synergistic cell killing by combination therapy of retinoic acid and hyperthermia in human epidermoid laryngeal carcinoma cells in culture

In vitro monolayer culture and clonogenic assay were used to investigate the individual and combined effect of temperature and retinoic acid (RA) on cellular morphology and colony forming ability of human epidermoid laryngeal carcinoma (HEp-2) cells. 20 micromol. RA alone inhibited multilayer formation and induced cell flattening. Hyperthermia (42 degrees C) individually caused formation of cytoplasmic processes and irregularities in cellular shape and size. Combined effect of hyperthermia (42 degrees C) and 20 micromol. RA treatment caused bleb formation on cell surfaces and lysis of cytoplasmic and nuclear membrane. RA treatment also caused dose-dependent reduction of colony growth. Heat-induced cell killing was only observed at lethal temperatures of 43 degrees C and above. RA in combination with heat synergistically inhibited colony formation even at non lethal temperatures of 41 and 42 degrees C. These results indicate that RA in combination with hyperthermia may facilitate the therapy of human epidermoid larynx carcinoma.

Singular anti-RNA virus-directed proteins

AIMS

To additionally purify and characterise the anti-RNA virus-directed protein termed p14.

MATERIALS AND METHODS

Antiviral assays of p14 against RNA and DNA viruses were carried out and its antigenic similarities with chicken interferon (CIFN) were studied. HPLC-Reverse Phase of p14 was performed to further purify p14.

RESULTS

p14 showed antiviral activity against RNA viruses only and not against DNA viruses. It was antigenically distinct from CIFN. Purification of p14 yielded three proteins with antiviral activity, which had different physico-chemical properties than those described for interferons.

CONCLUSIONS

The data presented on the antiviral, immunological and physico-chemical properties, establish the unique nature of p14 vis-á-vis those of interferons.

Outdoor work and the risk of pterygia: a case-control study

AIM

To investigate the relationship between outdoor work and pterygium formation in a hospital-based case-control study in Singapore.

METHOD

Sixty-one patients with pterygium (49 males, mean age 54.2 years) and 125 controls (41 males, mean age 50.2 years), excluding patients with cataract and age-related macular degeneration presenting at outpatient clinics of the Singapore National Eye Centre were interviewed face-to-face with a standard questionnaire. Demographic data and information on outdoor work and eye protection, were collected.

RESULTS

Thirty-eight subjects (20.4%) were outdoor workers and 148 (79.6%) were indoor workers. Outdoor workers were more likely to be male smokers and alcohol drinkers with lower family income and higher sunlight exposure than indoor workers. The crude odds ratio for pterygium in outdoor workers was 7.0 (95% confidence interval 3.2, 15.3). The adjusted odds ratio was 4.2 (95% confidence interval 1.7, 10.1).

CONCLUSION

There is a statistically significant association between outdoor work and pterygium formation, which may be related to the higher exposure to sunlight and dust in outdoor workers. Efforts may be made to educate outdoor workers to wear proper equipment to protect their eyes against excessive sunlight.

Separation of carrier-free hafnium and lutetium radionuclides produced in 16O activated terbium metal target

Charged particle activation with approximately 88 MeV 16O7+ beam on natural terbium metal foil leads to the production of the short lived carrier-free radioisotopes 170,171Ta and their corresponding daughter products 170,171Hf and 170,171Lu in the target matrix. Liquid-liquid extraction with HDEHP diluted in cyclohexane was carried out for the separation of 170,171Hf and 170,171Lu from the bulk terbium in an aqueous HCl medium.

Risk factors for the development of pterygium in Singapore: a hospital-based case-control study

PURPOSE

A hospital-based case-control study, designed to evaluate the risk factors for the development of pterygium in Singapore.

METHODS

Sixty-one cases and 125 controls were interviewed at the Singapore National Eye Centre. Information on present and past (5 and 10 years ago) exposure to sunlight on weekdays and weekends, sociodemographic data, behavior lifestyle and family history of eye disease was collected.

RESULTS

Patients with pterygia were mostly males, smoked and drank alcohol more often, had lower combined family incomes and were more likely to have a family history of eye disease. The adjusted odds ratios for the development of pterygia were 1.27 (95 percent confidence interval 1.06 to 1.54) and 1.31 (95 percent confidence interval 1.09 to 1.57) for participants who had spent more time in the sun five and ten years ago respectively.

CONCLUSIONS

Pterygium is an important public health problem in Singapore and its development is related to the amount of sunlight exposure.

High-resolution physical map and transcript identification of a prostate cancer deletion interval on 8p22

A genomic interval of approximately 1-1.5 Mb centered at the MSR marker on 8p22 has emerged as a possible site for a tumor suppressor gene, based on high rates of allele loss and the presence of a homozygous deletion found in metastatic prostate cancer. The objective of this study was to prepare a bacterial contig of this interval, integrate the contig with radiation hybrid (RH) databases, and use these resources to identify transcription units that might represent the candidate tumor suppressor genes. Here we present a complete bacterial contig across the interval, which was assembled using 22 published and 17 newly originated STSs. The physical map provides twofold or greater coverage over much of the interval, including 17 BACs, 15 P1s, 2 cosmids, and 1 PAC clone. The position of the selected markers across the interval in relation to the other markers on the larger chromosomal scale was confirmed by RH mapping using the Stanford G3 RH panel. Transcribed units within the deletion region were identified by exon amplification, searching of the Human Transcript Map, placement of unmapped expressed sequence tags (ESTs) from the Radiation Hybrid Database (RHdb), and from other published sources, resulting in the isolation of six unique expressed sequences. The transcript map of the deletion interval now includes two known genes (MSR and N33) and six novel ESTs.

Strategies for eradication of poliomyelitis--the Indian experience

Substantial progress has been made towards achieving global eradication of poliomyelitis by the end of the year 2000; the goal set by the World Health Assembly in May 1988. The basic strategies to eradicate polio are: attaining high routine coverage with at least three doses of OPV; conducting national immunization days (NIDs) in polio endemic countries; establishing a sensitive system of acute flaccid paralysis (AFP) surveillance to track wild poliovirus circulation; and conducting "mopping-up" immunization when polio is reduced to focal transmission. By the end of 2000. India was in the midst of the sixth National Immunization Days (NIDs). Surveillance system for Acute Flaccid Paralysis (AFP) continued to achieve the recommended non-polio AFP rate of at least 1 per 100,000 population < 15 years per year (1.88 for week 51 ending 23rd December 2000), the adequate stool specimen collection rate was 83% that met the target of > 80%. Some States in the south and west have started to implement mopping-up immunization campaigns as the end-stage strategy to eliminate the last remaining foci of transmission. While most of India appears to be well placed to eradicate polio by the end of 2000 or shortly thereafter, concerns remain about low coverage in parts of the densely populated northern States of Uttar Pradesh and Bihar where high intensity transmission persists. The Government of India has embarked upon an intensified strategy that relies on extra rounds of NIDs; house-to-house immunization to reach previously missed children; and aggressive mopping-up campaigns including pre-emptive mopping-up in the known reservoirs in Uttar Pradesh and Bihar. Extensive microplanning and supervision of the supplementary immunization activities is critical to achieve the target of polio eradication.

Surveillance for polio eradication: current status and lessons learnt--India, 1999

With the launch of the Universal Immunisation Programme in India in 1985, childhood immunisation was provided to children in all districts of the country in a phased manner by 1990. Surveillance for vaccine preventable diseases (VPD) including polio was started at the same time with monthly reporting from the districts to the Ministry of Health and Family Welfare (MOHFW), Government of India (GOI). In 1995, the Pulse Polio Immunisation (PPI) campaign was launched with the objective of polio eradication. Prior to 1997, surveillance for polio was directed at finding clinical polio cases by passive reporting from health facilities. There was no active surveillance for all cases of acute flaccid paralysis (AFP). In 1996, a scheme for the surveillance of AFP was drawn up. With the support of the Danish and US governments and Rotary International, 59 surveillance medical officers (SMOs) were hired, trained, and posted throughout the country in October 1997 to establish active surveillance of AFP. The number of SMOs was increased to 108 in August 1999. The SMOs along with their government counterparts established 10,069 reporting units nationwide by the end of November 1999 reporting weekly the occurrence of AFP cases to the district, state, and national levels; timely case investigation and collection of stool specimens from AFP cases; linkages to support the polio laboratory network; and extensive training of government counterparts. Data reported to the national level is analysed and put on an internet website which is updated every two weeks. Annualised rates of reported non-polio AFP have increased from 0.22 per 100,000 children aged < 15 years in 1997 to 1.57 in 1999. The number of polio cases associated with isolation of wild poliovirus decreased from 1404 in the third trimester of 1998 to 664 in the third trimester of 1999, yet widespread transmission of wild polioviruses persists throughout the country.

Poliomyelitis surveillance: the model used in India for polio eradication

Poliomyelitis surveillance in India previously involved the passive reporting of clinically suspected cases. The capacity for detecting the disease was limited because there was no surveillance of acute flaccid paralysis (AFP). In October 1997, 59 specially trained Surveillance Medical Officers were deployed throughout the country to establish active AFP surveillance; 11,533 units were created to report weekly on the occurrence of AFP cases at the district, state and national levels; timely case investigation and the collection of stool specimens from AFP cases was undertaken; linkages were made to support the polio laboratory network; and extensive training of government counterparts of the Surveillance Medical Officers was conducted. Data reported at the national level are analysed and distributed weekly. Annualized rates of non-polio AFP increased from 0.22 per 100,000 children aged under 15 years in 1997 to 1.39 per 100,000 in 1999. The proportion of cases with two adequate stools collected within two weeks of the onset of paralysis increased from 34% in 1997 to 68% in 1999. The number of polio cases associated with the isolation of wild poliovirus decreased from 211 in the first quarter of 1998 to 77 in the first quarter of 1999. Widespread transmission of wild poliovirus types 1 and 3 persists throughout the country; type 2 occurs only in Bihar and Uttar Pradesh. In order to achieve polio eradication in India during 2000, extra national immunization days and house-to-house mopping-up rounds should be organized.

Identification of a novel surface mutant of hepatitis B virus in a seronegative chronic liver disease patient

Hepatitis B virus (HBV) with mutations in the envelope proteins can emerge during natural infections, vaccinations or interferon therapy and appears occasionally to escape virus elimination or detection. The implications of such mutations at the molecular level are often obscure. We report the identification of a new surface mutant of HBV. This mutant was identified, and isolated from a chronic liver disease patient, negative for HBsAg as well as other serological markers but positive for HBV DNA. Several mutations were observed in the surface antigen gene out of which a Thr118-Ala118 change was predicted to have a destabilizing effect on the structural integrity of the 'a' determinant and also alter the antigenicity profile of the mutant HBsAg. Besides a RNA hairpin loop was predicted for the transcript generated by the small surface protein of this mutant, which could have an inhibitory effect at the translational level. These observations thus indicate that mutations in the surface gene could lead to a considerable decrease or complete absence of properly folded surface antigen which in turn could explain the absence of reactive HBsAg in the serum of the patient.

Dose related growth response to indometacin in Gitelman syndrome

Growth failure is a recognised feature of Gitelman syndrome, although it is not as frequent as in Bartter syndrome. Indometacin is reported to improve growth in Bartter syndrome, but not in Gitelman syndrome, where magnesium supplements are recommended. This paper presents 3 sisters with Gitelman syndrome who could not tolerate magnesium supplements, and whose hypotension and polyuria were eliminated by taking 2 mg/kg/day indometacin, but who grew poorly. However, increasing the indometacin dose to 4 mg/kg/day improved their growth significantly, without changing their symptoms or biochemistry. Gastrointestinal haemorrhage necessitated the use of misoprostol.

Differential effects of ethanol on insulin-signaling through the insulin receptor substrate-1

Insulin stimulation increases cell proliferation and energy metabolism by activating the insulin receptor substrate I (IRS-1)-signaling pathways. This downstream signaling is mediated by interactions of specific tyrosyl phosphorylated (PY) IRS-1 motifs with SH2-containing molecules such as growth-factor receptor-bound protein 2 (Grb2) and Syp. Ethanol inhibits insulin-stimulated tyrosyl phosphorylation of IRS-1 and DNA synthesis. This study explores the roles of the Grb2- and Syp-binding motifs of IRS-1 in relation to the inhibitory effects of ethanol on insulin-stimulated DNA synthesis, proliferating cell nuclear antigen (PCNA) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) expression, and activation of mitogen-activated protein kinase (MAPK), which is known to be essential for cell proliferation. NIH3T3 cells were stably transfected with wild-type IRS-1, or IRS-1 mutated at the Grb2 (IRS-1deltaGrb2), Syp (IRS-1deltaSyp), or Grb2 and Syp (IRS-1deltaGrb2deltaSyp)- binding sites. Cells transfected with IRS-1 had increased levels of DNA synthesis, PCNA, GAPDH, and activated MAPK. The IRS-1deltaGrb2 transfectants were highly responsive to insulin stimulation, achieving levels of GAPDH, PCNA, and activated MAPK that were higher than control. In contrast, the IRS-1deltaSyp and IRS-1deltaGrb2deltaSyp transfectants had reduced levels of DNA synthesis, PCNA, and activated MAPK. Ethanol exposure decreased insulin-stimulated DNA synthesis, PCNA, GAPDH, and activated MAPK levels in all clones, but the wild-type IRS-1 transfectants were relatively resistant, and the IRS-1deltaGrb2 transfectants were extraordinarily sensitive to these inhibitory effects of ethanol. The findings suggest that insulin-stimulated DNA synthesis and PCNA expression are mediated through the Syp-binding domain, whereas GAPDH expression and MAPK activation are modulated through both the Grb2 and Syp motifs of IRS-1. In addition, ethanol exposure may preferentially inhibit downstream signaling that requires interaction between Syp and PY-IRS-1.

Epstein-Barr virus in nasopharyngeal carcinoma in Indian patients

Formalin fixed paraffin embedded tissue blocks from 40 cases of nasopharyngeal carcinoma were investigated for the presence of Epstein-Barr virus (EBV). Heminested polymerase chain reaction was employed to amplify U 2 region of EBV DNA coding for EBNA 2 gene. This is the first study of its kind carried out in India. EBV was detected in 28 out of 40 (70%) nasopharyngeal carcinomas. Type A EBV was identified in 20 cases (71.4%), type B in 7 cases (25%) and coinfection in one case (3.5%). Either type A, or type B EBV, was identified in 22 out of 23 cases (95.7%) of undifferentiated nasopharyngeal carcinoma and 6 out of 15 cases (40%) of non keratinized squamous carcinoma. The higher incidence of EBV in non keratinized squamous carcinoma of nasopharynx assumes importance in view of the contrary reports in other studies. 26 cases were from Western India, of which 15 (57.6%) showed presence of type A EBV and 2 (7.6%) type B EBV. From Eastern Indian particularly Assam, 4 our of 5 cases showed positivity for type B EBV and 1 a coinfection. Whereas, from Bihar 3 out of 4 cases showed presence of type A EBV. From Middle East (Arabs) type A EBV was detected in 3 out of 5 cases of nasopharyngeal carcinomas. Geographically, type A EBV was far more prevalent in Western India, while in Eastern India particularly Assam, all five vases were positive for type B EBV. Thus, a significant variation in the type of EBV infection was observed in nasopharyngeal carcinoma in different ethnic populations in India.

Near-field optical studies of local photomodification in nanostructured materials

Fractal aggregates of silver nanoparticles are studied experimentally using atomic force microscopy and photon scanning tunnelling microscopy. Large changes in the near-field optical response of fractal aggregates are observed after the irradiation of samples with nanosecond laser pulses. The threshold energy density for photomodification using a 532 nm laser is measured to be 9 mJ cm(-2). It is shown that photomodification-induced changes in the local optical response can be two orders of magnitude larger than changes in far-field absorption.