Adaptive mechanisms induced by long-term estrogen deprivation in breast cancer cells

Clinical observations suggest that human breast tumors can adapt in response to endocrine therapy by developing hypersensitivity to estradiol. To understand the mechanisms responsible, we examined estrogenic stimulation of cell proliferation in a model system and provided evidence that long-term deprivation of estradiol causes adaptive hypersensitivity. The enhanced responses to estradiol do not involve mechanisms acting at the level of transcription of estrogen regulated genes. We found no evidence of hypersensitivity when examining the effects of estradiol on regulation of c-myc, pS2, progesterone receptor, several ER reporter genes or c-myb in hypersensitive cells. On the other hand, deprivation of breast cells long term was found to up-regulate a separate pathway whereby the estrogen receptor co-opts a classical growth factor pathway and induces rapid non-genomic effects. Through this pathway, estradiol caused rapid activation of mitogen-activated protein (MAP) kinase. In exploring the mechanisms mediating this event, we found that estradiol binds to cell membrane associated estrogen receptors and causes phosphorylation of Shc, an adaptor protein usually involved in growth factor signaling pathways. ERalpha was found to complex with Shc under these conditions. In turn, Shc bound Grb-2 and Sos which resulted in the activation of MAP kinase. The pure antiestrogen, ICI 182,780, blocked several steps in the rapidly responding ER alpha, Shc, MAP kinase pathway. These non-genomic effects of estradiol produced biologic effects by activating Elk and by inducing morphologic changes in cell membranes. Using confocal microscopy, we demonstrated that estradiol caused a rapid alteration in membrane ruffling, the formation of pseudopodia and translocation of ER alpha to regions contiguous with the cell membrane. These morphologic effects could be blocked with a pure anti-estrogen. We conclude that long-term estradiol deprived cells utilize both genomic (transcriptional) and rapid, non-genomic estradiol induced pathways. We postulate that synergy between these two pathways acting at the level of the cell cycle is responsible for adaptive hypersensitivity.

Regulation of osteoblast growth by interactions between transforming growth factor-beta and 1alpha,25-dihydroxyvitamin D3

Osteoblast growth and differentiation encompass a series of events including proliferation, changes in cell shape, and expression of the markers specific for osteoblast phenotype. Both transforming growth factor-beta (TGF-beta) and 1alpha,25-dihydroxyvitamin D3 (1alpha,25[OH]2D3) are effective in regulating osteoblast proliferation, differentiation, bone matrix maturation and cell-specific gene expression. Although there is some degree of controversy regarding the influences on osteoblasts in vitro, it is generally agreed that TGF-beta stimulates osteoblast proliferation and growth, and inhibits the expression of the markers characteristic of the osteoblast phenotype such as osteocalcin. In contrast, 1alpha,25(OH)2D3 causes inhibition of the proliferation of osteoblasts, arrests their growth, and stimulates expression of specific markers. In many studies, complex interactions have been demonstrated between TGF-beta and 1alpha,25(OH)2D3 modulating their receptor expression, synthesis, and effects on osteoblast-specific gene expression. The cooperative actions of TGF-beta and 1alpha,25(OH)2D3 can be synergistic or antagonistic. It has recently been established that Smad proteins that transduce signals downstream the TGF-beta stimulation may mediate the crosstalk between TGF-beta and 1alpha,25(OH)2D3 signaling. Future studies should focus on the explanation of the molecular basis of these interactions and the in vivo consequences of the regulation of osteoblast growth and differentiation by TGF-beta and 1alpha,25(OH)2D3.

Allergenic cross-reactivity of Curvularia lunata with other airborne fungal species

BACKGROUND

Curvularia lunata is an important fungus for respiratory allergic disorders. Previous studies indicated cross-reactivity of Curvularia with other fungi. However, the cross-reactive allergenic component (s) were not identified. The present work was carried out to study the shared allergenic components of C. lunata and others.

METHODS

Cross-reactivity studies were performed using pooled hypersensitive patient sera to C. lunata by ELISA, immunoblot, immunoblot inhibition and ELISA inhibition.

RESULTS

Many C. lunata sensitive patients showed positive skin test to five other fungi. Alternaria alternata exhibited maximum (68%) whereas Cladosporium herbarum showed the least (17%) skin reactivity. Immunoblots of fungal extracts with pooled sera showed common proteins. Fusarium solani and C. herbarum showed negligible IgE binding. IgE ELISA inhibition with C. lunata showed 92% inhibition whereas A. alternata and E. nigrum showed 84% and 63%, respectively. Immunoblot inhibition with self protein showed complete loss of IgE-binding activity. Proteins of 26, 31, 38, 45 and 50 kDa of C. lunata were inhibited by A. alternata and E. nigrum, whereas A. fumigatus inhibited 26, 45 and 50 kDa proteins.

CONCLUSIONS

Significant allergenic cross-reactivity exists among proteins of C. lunata, A. alternata and E. nigrum. Proteins of 26, 31, 38, 45 and 50 kDa are shared allergens in these fungi.

MR imaging and in vivo proton spectroscopy of the brain in neonates with hypoxic ischemic encephalopathy

INTRODUCTION

A number of studies have suggested the potential utility of in vivo proton MR spectroscopy for the evaluation of brain injury in the asphyxiated neonates. We present our initial experience with in vivo proton MR spectroscopy in neonates who were diagnosed as having hypoxic injury on clinical examination and the severity of the insult was graded using Sarnat staging.

METHODS AND MATERIAL

MR imaging and in vivo proton MR spectroscopy was performed in 16 neonates with hypoxic ischemic encephalopathy (HIE) to correlate the imaging and metabolite abnormality with clinical severity of the condition at the time of insult and with outcome at 2 months of age. The ratios of different metabolites were calculated as observed on MR spectroscopy from an 8 ml voxel that included thalami, basal ganglia and part of the ventricular system using spin echo technique with an echo time of 135 ms.

RESULTS AND DISCUSSION

The results of the spectroscopy were compared with imaging abnormalities and Sarnat's clinical staging of HIE. MR Imaging abnormalities included basal ganglia, thalamic and periventricular hemorrhage and periventricular hyperintensities and were noticed in 8/16 neonates with different stages of HIE. Maximum imaging abnormalities were noted in stage II (6/9) followed by stage III (1/2) and stage I (1/5), respectively. The alpha-Glx resonance at 3.76 ppm was seen in 14/16, Glycine at 3.56 ppm (Gly) was seen in 10/16 and Lactate (L) at 1.33 ppm was observed in 4/16 neonates with HIE.

CONCLUSION

MR spectroscopy was more sensitive than imaging in detecting the insult due to HIE and increased concentration of alpha-Glx/Cr and Gly/Cr correlated better with severity of the HIE. The demonstration of L was associated with poor outcome.

Ketamine dependence

Ketamine hydrochloride is a safe and rapid-acting non-opioid, lipid soluble anaesthetic with a short elimination half-life that is used for medical and veterinary purposes. It produces a state of "dissociative anaesthesia", probably from action on N-methyl-D-aspartate (NMDA) receptors. The psychotropic effects of ketamine range from dissociation and depersonalization to psychotic experiences and include a sensation of feeling light, body distortion, absence of time sense, novel experiences of cosmic oneness and out-of-body experiences. Abuse of ketamine has been reported, the typical abuser being an individual who uses multiple drugs and has some contact with medical agencies. This case demonstrates the effects of large doses of ketamine in a person with polysubstance abuse. The case also highlights development of significant tolerance to ketamine without prominent withdrawal symptoms. Caution in use of ketamine is reiterated in light of its abuse liability.

Knowledge and practice pattern of non-allopathic indigenous medical practitioners regarding tuberculosis in a rural area of India

OBJECTIVE

To assess the knowledge and practice patterns of non-allopathic indigenous medical practitioners (IMPs) regarding tuberculosis (TB).

METHODS

Seventy-four IMPs practising in Naraingarh block, a rural area of Haryana State, India, were interviewed using a semi-structured interview schedule.

RESULTS

Fifty-four per cent (40/74) of the IMPs saw two to five TB patients every month. Sixty-one per cent (46/74) reported that they based their diagnosis of TB on symptoms alone, whereas 38% use diagnostic tests such as chest X-ray, erythrocyte sedimentation rate and sputum examination. Forty per cent of the IMPs reported that alcohol was the cause of TB, 36.5% cited smoking and 17.6% reported infection as the cause. Only 34% (25/74) of IMPs reported that they treated TB patients, while the rest said that they referred such cases to nearby hospitals. Anti-tuberculosis drugs used by IMPs were isoniazid, rifampicin and streptomycin, but none of them knew the dosage of the drugs, the duration of treatment or the correct regimen. Sixty-four per cent of the 25 IMPs reported using ayurvedic medicines.

CONCLUSION

Considerable proportions of TB patients seek IMPs for cure of TB, while the knowledge and practice of IMPs is inadequate.

Effect of vitamin A supplementation on childhood morbidity and mortality

In a double blind design, 1520 children aged < 10 years were individually randomised in vitamin A and placebo group in slums of Chandigarh. Children > 12, 6-12 and < 6 months of age received 200,000, 100,000, 500,000 I.U. of vitamin A respectively every 4 to 6 months during 15 months trial period. The prevalence of vitamin A deficiency was significantly reduced in vitamin A compared to placebo group during the follow-up period. In vitamin A group, incidence of diarrhoea and measles was significantly reduced but incidence of acute respiratory infections was not significantly different compared to control group. Risk of death was also significantly less in vitamin A group. Therefore, promotion of vitamin A rich diet or supplementation with synthetic vitamin A at 4-6 month interval should be a priority in populations where risk of vitamin A deficiency is high.

Construction of an RAPD linkage map and localization of QTLs for oleic acid level using recombinant inbreds in mustard (Brassica juncea)

RAPD markers were employed for construction of a linkage map and localization of QTLs for oleic acid level using a set of 94 recombinant inbred lines (RILs) of mustard (Brassica juncea L.) as a mapping population. Only 30% of the 235 random primers used were useful in terms of polymorphism detected and the reproducibility of those patterns. Normal Mendelian segregation was observed for the majority of the 130 markers obtained with 71 informative primers; only 13.1% deviated (P < 0.01) from the expected 1:1 ratio. One-hundred and fourteen markers were assigned to 21 linkage groups (LGs) covering a total length of 790.4 cM with an average distance of 6.93 cM between markers. Two quantitative trait loci (QTL) for oleic acid level were mapped to 14- and 10.6-cM marker intervals on two different LGs. Both loci together explained 32.2% of phenotypic variance. One major QTL explained 28.5% of the trait variance observed in this species.

Synthesis and biologic activity of a C-ring analog of vitamin D3: biologic and protein binding properties of 11.alpha.-hydroxyvitamin D3

The influence of C-ring substituents on the biologic activity and protein binding properties of vitamin D3 has not been systematically investigated. To this end, we dehydrogenated cholesta-5,7-dien-3 beta-ol (1) to the 5,7,9(11)-triene. After protection of the 5,7-diene with a 4-phenyl-1,2,4- triazoline -3,5-dione Diels -Alder adduct, oxidation of the unprotected 9(11)-olefin gave epoxide 5. Reverse Diels -Alder and reductive ring opening of epoxide 5 gave cholesta-5,7-diene-3 beta, 11 alpha-diol (6). Photolysis of 6 to the previtamin followed by thermal rearrangement resulted in 11 alpha-hydroxyvitamin D3 (8). We found that vitamin 8 increased calcium transport at a dose of 500 pmol/rat but failed to increase bone calcium mobilization at a dose as high as 50 000 pmol/rat. Under the same conditions, corresponding doses of vitamin D3 and 25-hydroxyvitamin D3 increased bone calcium mobilization and intestinal calcium transport. The new vitamin analogue, 8, was slightly less efficient (B-50 = 6.8 X 10(-8) M) than 25-hydroxyvitamin D3, 24(R),25-dihydroxyvitamin D3, and 25-(S), 26-dihydroxyvitamin D3 (7.1 X 10(-9) M, 7.7 X 10(-9) M, and 7.9 X 10(-9) M, respectively) in displacing radiolabeled 25-hydroxyvitamin D3 from rat plasma vitamin D binding protein. On the other hand, vitamin analogue 8 showed significantly greater binding efficiency than 1 alpha-hydroxyvitamin D3, 1,25-dihydroxyvitamin D3, and vitamin D3 (B-50 = 2.5 X 10(-6) M, 9.84 X 10(-8) M, and 5.46 X 10(-7) M, respectively), under these same conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

Autocrine production and synergistic growth-promoting activity of interleukin-6 and oncostatin M in a new human myeloma cell line TU-1

Human myeloma cell lines are difficult to establish, and they usually originate from patients with extramedullary disease. We describe a new human myeloma cell line, TU-1, which was established from the bone marrow of a patient without extramedullary myeloma. The myeloma cells were initially maintained in a conditioned medium derived from another well-known myeloma cell line U-266. This conditioned medium contained interleukin-6 (IL-6) and oncostatin M (OSM), and possibly other unknown growth factors as well. In 3 months the TU-1 cell line proliferated autonomously and secreted IL-6 and OSM with a synergistic growth response. As we have previously shown the cell line acquired a p53 mutation in vitro, which may be an important factor causing autonomous proliferation. In patients with multiple myeloma OSM is frequently found in the serum and OSM has been associated with serum IL-6 and progressive disease. Our study demonstrates the close relationship of OSM and IL-6 also in vitro.

Spina bifida occulta in isthmic spondylolisthesis: a surgical trap

An 11-year-old girl presented with symptomatic grade IIB isthmic type spondylolisthesis, with an elongated pars, confirmed on magnetic resonance imaging (MRI). Posterolateral in situ fusion of L5/S1 was performed. At surgery, a significant bony defect in the posterior aspect of S1 was noted. Awareness of this possible co-existence is paramount if iatrogenic damage to neural elements is to be avoided during surgery.

Multiparametric quantitation of the perilesional region in patients with healed or healing solitary cysticercus granuloma

The purpose of this study was to compute T2 values and magnetization transfer (MT) ratios in the perilesional region of healing and healed cysticercus granulomas to determine if there are T2 abnormalities not apparent on conventional T2-weighted imaging and to determine the relationship between seizure control and the quantitative measures. Sixty-three patients were studied. T2 values and MT ratios were computed for the perilesional region and were compared with measurements from the contralateral normal-appearing region. A significantly increased T2 value was found for the perilesional region compared to the corresponding contralateral region despite the absence of qualitative abnormality on conventional T2-weighted magnetic resonance imaging. For patients showing normal-appearing perilesional regions on MT imaging, there was no significant difference in T2 and MT ratios between the perilesional and the normal contralateral regions. There was a statistically significant inverse correlation between perilesional T2 values and MT ratios, suggesting each was associated with perilesional gliosis. The study illustrates that quantitative evaluation of MT ratios and T2 augments the qualitative visual assessment of the perilesional region in healing or healed cysticercus granulomas.

Epidemic dropsy: observations on pathophysiology and clinical features during the Delhi epidemic of 1998

Epidemic dropsy results from the consumption of edible oils adulterated with Argemone mexicana oil by unscrupulous traders. Twenty consecutive 'in-door' patients of dropsy were intensively studied during the recent Delhi epidemic. Samples of edible oil used by them, their urine and their serum samples tested positive for sanguinarine on thin layer chromatography. The illness starts as a gastro-enteric illness followed by oliguria and pedal oedema. The following are often observed: cutaneous erythema with blanching and tenderness on pressure; violacious pigmentation of the skin; shortness of breath with orthopnoea; right-sided heart failure with normal left ventricle (LV) functions; as well as severe anaemia and hypoalbuminaemia. Renal function tests showed: bland urinary sediments; decreased glomerular filtration rate (GFR); mild to moderate azotaemia; acute tubular necrosis; patchy pneumonitis; moderate hypoxia with respiratory alkalosis; and restrictive ventilatory defects on blood gas analysis; and spirometry suggestive of interstitial pulmonary oedema of non-cardiogenic origin. 99mTc colloid sulphur liver scans showed colloid shift. There was marked dilatation and proliferation of dermal capillaries in the absence of significant inflammation in the biopsy specimens. Toxic alkaloids of Argemone mexicana oil induce widespread capillary dilatation and permeability causing leakage of protein rich plasma into the interstitial tissues of various organs. A hypovolaemic state is thus induced producing renal hypoperfusion which may progress to acute tubular necrosis. Interstitial fluid in alveoli causes restrictive ventilatory dysfunction with hypertension and right-sided failure with well-preserved LV function. The hepatic venous congestion induces Kupffer's cell dysfunction, which results in colloid shift on a radionuclide liver scan.

Intrabiliary rupture of hydatid cyst: diagnosis with MRI and hepatobiliary isotope study

Intrabiliary rupture is the most common complication of hepatic hydatid cyst yet it is unusual, occurring in only 3-17% of cases. The diagnosis is rarely difficult on ultrasound and CT when typical radiological features are present. In rare cases of complete evacuation, when characteristic findings of hydatid cyst are absent or when there is no evidence of the previous existence of liver hydatid cyst, the diagnosis may be difficult. In difficult cases, MRI, MRCP, ERCP and (99)Tc(m)-mebrofenin hepatobiliary scintigraphy are employed. We present a rare case of surgical obstructive jaundice due to rupture of a liver hydatid cyst into the biliary tract and gall bladder, with complete evacuation of its contents leading to misdiagnosis on CT and ultrasound. MRCP and (99)Tc(m)-mebrofenin hepatobiliary scintigraphy were able to establish a firm pre-operative diagnosis.

Monitoring of seasonal vegetables for pesticide residues

Market samples (60) of six seasonal vegetables were monitored during 1996-1997 to determine the magnitude of pesticidal contamination. The estimation of insecticide residues representing four major chemical groups i.e. organochlorine, organophosphorous, synthetic pyrethroid and carbamate, was done by adopting a multiresidue analytical technique employing GC-ECD and GC-NPD systems with capillary columns. The tested samples showed 100% contamination with low but measurable amounts of residues. Among the four chemical groups, the organophosphates were dominant followed by organochlorines, synthetic pyrethroids and carbamates. About 23% of the samples showed contamination with organophosphorous compounds above their respective MRL values. More extensive studies covering different regions of Haryana state are suggested to get a clear idea of the magnitude of vegetable contamination with pesticide residues.

Role of Oxalobacter formigenes in calcium oxalate stone disease: a study from North India

OBJECTIVE

The present study was performed to detect the presence of an oxalate degrading bacteria Oxalobacter formigenes in the GI tract of calcium oxalate stone patients and normal individuals from North India. Furthermore, the possible relationship of this bacterium with number of stone episodes in this part of the world was also studied. The correlation of the presence or absence of O. formigenes with the urinary oxalate levels was evaluated.

METHODS

DNA was extracted from the stool samples of 63 calcium oxalate stone formers and 40 normal individuals. Polymerase chain reaction (PCR) was performed using genus specific primers for O. formigenes. The presence of which was confirmed by Southern blotting. Urinary oxalate levels were tested in each patient.

RESULTS

As shown by PCR and Southern blotting, O. formigenes was present in 65% of normal individuals and in 30% of calcium oxalate stone formers. In patients with three or greater than three stone episodes colonies were present only in 5.6% of patients. Oxalate excretion was less in patients colonized with O. formigenes as compared to those with no colonization.

CONCLUSION

In North Indian population the absence of O. formigenes can lead to a significant increase in the risk of absorptive hyperoxaluria and resultant recurrent calcium oxalate stone episodes.

Isolated and multisystem hepatic trauma in children: the true role of non-operative management

We retrospectively reviewed children with hepatic injuries (HI) admitted to our institutions from January 1982 to December 1999. Specific comparison was made of isolated (IHT) and multisystem hepatic trauma (MHT). Over the 18-year period 127 patients were identified with HI, 91 (71%) with MHT and 36 with IHT. The median age was 8 years (range 13 months to 14 years). Motor vehicle injury was the most common mechanism in both groups, but bicycle injuries were more common in IHT ( P<0.001). Shock ( P=0.02), the requirement for blood transfusion ( P<0.001), and operative intervention for the HI ( P=0.001) were all significantly more common in MHT. The distribution of liver injury grades was similar between the two groups. Twenty-two (17.3%) children died and in 18 the HI was the main cause or contributed significantly. There were 19 and 3 deaths in the MHT and IHT groups, respectively, a difference that was not significant. After excluding children with minor HI, 27 (39%) required operative intervention within 24 h of their injury. This suggests that the high success rate for non-operative management of HIs in the literature may have been biased by the inclusion of a significant proportion of subclinical injuries.

The Localio approach: a technical note for a large sacral chordoma

Whenvever possible, radical resection of retrorectal tumours should be performed.(1) We describe the Localio technique (abdominosacral approach) in a case of a large malignant sacral chordoma. We emphasise the necessity to perform such an approach to achieve a radical resection for these tumours which have little chemosensitivity and minimal radiosensitivity. We highlight clinical features which suggest the presence of a spinal tumour and reiterate the absolute importance of rectal examination.

Aerosol scavenging: model application and sensitivity analysis in the Indian context

Sulfate aerosols have been found to be the major contributors to precipitation acidity. Thus, in view of the long-term ecological repercussions they have on aquatic ecosystems and their acidity-potential, the present analysis focuses on a case study application of the layer-averaged aerosol-scavenging model (Okita et al., 1996) for predicting values of the wet scavenging coefficient and sulfate concentrations in precipitation samples on the basis of the information available for some selected Indian cities. Through sensitivity analysis (Pandey et al., 1997) the scavenging coefficient has been found to be very strongly dependent on precipitation intensity. Comparison of model predictions has been done with the measured values for Delhi, Mumbai, Calcutta and Chennai in India.