Reversal of catecholamine induced cardiomyopathy in a patient with bilateral malignant pheochromocytoma

A patient of catecholamine induced cardiomyopathy (CMP) due to bilateral malignant adrenal pheochromocytoma (PCC), successfully reversed on treatment is described here. To the best of our knowledge, this is first report of catecholamine induced CMP due to bilateral malignant adrenal PCC, which could be reversed after surgery.

Multicentric clinical trials for safety and efficacy evaluation of alpha;beta arteether in complicated P. falciparum malaria

OBJECTIVE

To evaluate efficacy of alpha;beta arteether in patients of P. falciparum malaria presenting with complications was undertaken in a multicentric clinical trial.

METHOD

Each patient who consented to undergo clinical trial with parenteral Arteether was treated with a fixed dose schedule of Arteether given intramuscularly in a dose of 150 mg once a day on three consecutive days. Every patient was followed upto 28 days with clinical, haematological and parasitological monitoring every day upto one week and thereafter at 14, 21 and 28 days. The response was assessed in terms of fever clearance time, parasite clearance time, cure rate and parasite reappearance rate.

RESULTS

A total of 211 patients of P. falciparum malaria were included in the study from four centres (Bhilai, Guwahati, Jamshedpur and Rourkela). Results of this study showed that fever clearance time ranged between 24-168 hours, parasite clearance time ranged between 24-120 hours and overall mortality ranged between 4-8.5%. Out of 211, only 14 patients expired during the study, of these, 10 patients expired within first two days i.e. before completing the three day schedule of arteether therapy. Tolerability to arteether injection was good in all these patients and no untoward effects were experienced or reported during the study. Overall cure rate observed in these studies was 93%.

CONCLUSION

This study shows a rapid parasite and fever clearance in patients of complicated P. falciparum malaria.

Dynamic chromatin remodeling on the HER2 promoter in human breast cancer cells

Deregulation of the HER2 oncogene occurs in 30% of human breast cancers and correlates with poor prognosis and increased propensity for metastasis. Since the molecular basis of HER2 overexpression in human cancers is not known, we sought to determine whether chromatin remodeling pathways are involved in the regulation of HER2 expression. We report that compared with breast cancer cells expressing a low level of HER2, HER2-overexpressing breast cancer cells contained significantly higher levels of acetylated and phosphorylated histone H3, and acetylated histone H4 associated with the HER2 promoter. Decreased recruitment of histone deacetylases in the promoter is also noted in the HER2-overexpressing cell. The association of acetylated histone H4 with HER2 gene chromatin and HER2 expression in breast cancer cells was upregulated by an inhibitor of histone deacetylases. Treatment with histone deacetylase inhibitor also reduced the association of histone deacetylase-1 and -2 with the HER2 promoter. In addition, the tumor promoters 12-O-tetradecanoylphorbol-13-acetate and okadaic acid stimulated the association of phosphorylated histone H3 on serine 10 with the HER2 promoter and also stimulated HER2 expression. These findings identify histone acetylation and histone phosphorylation as novel regulatory modifications that target HER2 gene chromatin, and suggest that elevated levels of these chromatin-relaxing components in the vicinity of the HER2 gene promoter may constitute an important non-genomic mechanism of HER2 overexpression in human breast cancer.

Thyroid nodules in Graves' disease: implications in an endemically iodine deficient area

BACKGROUND AND AIM

The presence of thyroid nodules with Graves' disease raises concern about co-existent thyroid malignancy. The objective of this study is to evaluate the risk of thyroid carcinoma and the need for surgical intervention in, patients with Graves' disease with co-existent nodules in an endemically iodine deficient area (IDA).

SUBJECTS AND METHODS

Retrospective study of 130 surgically managed patients of Graves' disease (1990-1999). Out of these 35 (26.9%) cases had palpable nodules. No patient had history of previous head and neck irradiation or radioiodine therapy. The clinico-pathological findings and follow-up of these cases were noted.

RESULTS

Mean age of patients with nodules was 40.2 +/- 9.5 years and male to female ratio was 1:2.2. The overall incidence of thyroid carcinoma in Graves' disease was 6.2% (8/130 cases), while the incidence, in cases having nodule with Graves' disease was 17.1% (6/35 cases). The median age of patients with carcinoma was 45 years (5 women and 1 man). Besides laboratory investigations for hyperthyroidism, preoperative investigations included fine needle aspiration cytology (FNAC) and thyroid scintigraphy in 29 and 25 cases respectively. Incidence of malignancy in palpable cold nodules was 20%. FNAC could not predict malignancy with certainty in any of these cases. Five patients had papillary thyroid carcinoma while one had follicular carcinoma. Median tumour diameter was 10 mm. Tumour was multi-centric in two cases while one case had metastases to cervical lymph node. In follow-up (median =5.5 years) one patient died of unrelated cause, while rest are alive with no evidence of disease.

CONCLUSIONS

Nodules are frequently associated with Graves' disease in IDA. Incidence of carcinoma is high in palpable cold nodule. We recommend early thyroidectomy in these cases.

An ab initio study of electronic structure and spectra of 8-bromoguanine: a comparative study with guanine

Ground state geometries of the four tautomeric forms keto-N9H, keto-N7H, enol-N9H and enol-N7H of 8-bromoguanine (8BG) were optimized using the ab initio RHF procedure employing a mixed basis set consisting of the 6-311 + G* basis set for the nitrogen atom of the amino group and the bromine atom, and the 4-31G basis set for all other atoms. These calculations were followed by correlation correction of the total energy at the MP2 level using the same basis set. The different tautomeric forms of 8BG in the ground state were solvated using the isodensity surface polarized continuum model (IPCM) of the SCRF theory both at the RHF and MP2 levels. Excited states were generated employing configuration interaction among singly excited configurations (CIS) obtained using a limited window of filled and empty molecular orbitals. Formation of hydrogen-bonded complexes between 8BG and three water molecules in the ground and excited states was considered in order to account for solvent effects approximately. Excited state geometry was optimized in each case for the lowest singlet excited state which was found to be of pi-pi* type. Vibrational frequency analysis was performed in order to ensure that the stationary points located on the potential energy surfaces by geometry optimization were minima. It is found that 8BG would occur in the ground state dominantly in the keto-N7H form both at the aqueous solution-air interface and inside the bulk liquid. The observed absorption and fluorescence spectra of 8BG can be explained satisfactorily considering only the keto-N7H form of the molecule. The enol tautomers of 8BG do not appear to be important from the point of view of ground state properties or electronic spectra. The observed differences between the behaviors of guanine and 8BG can be easily explained on the basis of the results obtained.

Parathyroid carcinoma

INTRODUCTION

Parathyroid carcinoma is a rare tumor with an incidence of 0.5 to 4%. Preoperative differentiation from benign adenoma is very difficult. Several features, though nonspecific, have been used in differentiating parathyroid carcinoma from the adenoma.

MATERIAL AND METHOD

A retrospective analysis during the period of nine years, four cases of parathyroid carcinoma were diagnosed on the basis of per-operative local invasion and on histological evidence of capsular invasion and vascular invasion.

RESULT

We have different observations to make. Diagnosis of parathyroid carcinoma which was done on the basis of intra operative suspicion only. One patient died on 6th post operative day due to development of pancreatitis. At the follow-up of two years there was no local recurrence or distant metastasis.

CONCLUSION

It is preferable to have a high index of suspicion for parathyroid carcinoma when these features are present than to miss the opportunity for surgical cure by failing to consider it in the differential diagnosis.

Benign thymic hyperplasia after chemotherapy for acute myeloid leukemia

Thymic hyperplasia can occur after cytotoxic therapy for various malignancies. The possible cause could be rebound enlargement after initial atrophy caused by these drugs. During the treatment of hematological malignancies this could be a cause of great concern. We report here a case of thymic hyperplasia after chemotherapy for acute myeloid leukemia. Awareness of this unusual side-effect may prevent needless investigation and therapy.

Shear stress enhances microcin B17 production in a rotating wall bioreactor, but ethanol stress does not

Stress, including that caused by ethanol, has been shown to induce or promote secondary metabolism in a number of microbial systems. Rotating-wall bioreactors provide a low stress and simulated microgravity environment which, however, supports only poor production of microcin B17 by Escherichia coli ZK650, as compared to production in agitated flasks. We wondered whether the poor production is due to the low level of stress and whether increasing stress in the bioreactors would raise the amount of microcin B17 formed. We found that applying shear stress by addition of a single Teflon bead to a rotating wall bioreactor improved microcin B17 production. By contrast, addition of various concentrations of ethanol to such bioreactors (or to shaken flasks) failed to increase microcin B17 production. Ethanol stress merely decreased production and, at higher concentrations, inhibited growth. Interestingly, cells growing in the bioreactor were much more resistant to the growth-inhibitory and production-inhibitory effects of ethanol than cells growing in shaken flasks.

A multicentric study with arteether in patients of uncomplicated falciparum malaria

Two hundred and sixty seven patients of uncomplicated P. falciparum malaria completed study in a multicentric phase III clinical trial of Arteether. Arteether was given intramuscularly in a dose of 150 mg daily for three consecutive days. Each patient was followed upto 28 days of alpha, beta arteether therapy. The cure rate was 97% with fever clearance time between 1-7 days (24-168 hours) and parasite clearance time between 1-3 days (24-72 hours). Parasite reappearance rate was found to be 3% and reported at only three of the centres. Following the treatment no adverse effect was observed on haematological, biochemical and vital clinical parameters.

Arabidopsis and the heat stress transcription factor world: how many heat stress transcription factors do we need?

Sequencing of the Arabidopsis genome revealed a unique complexity of the plant heat stress transcription factor (Hsf) family. By structural characteristics and phylogenetic comparison, the 21 representatives are assigned to 3 classes and 14 groups. Particularly striking is the finding of a new class of Hsfs (AtHsfC1) closely related to Hsf1 from rice and to Hsfs identified from frequently found expressed sequence tags of tomato, potato, barley, and soybean. Evidently, this new type of Hsf is well expressed in different plant tissues. Besides the DNA binding and oligomerization domains (HR-A/B region), we identified other functional modules of Arabidopsis Hsfs by sequence comparison with the well-characterized tomato Hsfs. These are putative motifs for nuclear import and export and transcriptional activation (AHA motifs). There is intriguing flexibility of size and sequence in certain parts of the otherwise strongly conserved N-terminal half of these Hsfs. We have speculated about possible exon-intron borders in this region in the ancient precursor gene of plant Hsfs, similar to the exon-intron structure of the present mammalian Hsf-encoding genes.

Arabidopsis and the heat stress transcription factor world: how many heat stress transcription factors do we need?

Sequencing of the Arabidopsis genome revealed a unique complexity of the plant heat stress transcription factor (Hsf) family. By structural characteristics and phylogenetic comparison, the 21 representatives are assigned to 3 classes and 14 groups. Particularly striking is the finding of a new class of Hsfs (AtHsfC1) closely related to Hsf1 from rice and to Hsfs identified from frequently found expressed sequence tags of tomato, potato, barley, and soybean. Evidently, this new type of Hsf is well expressed in different plant tissues. Besides the DNA binding and oligomerization domains (HR-A/B region), we identified other functional modules of Arabidopsis Hsfs by sequence comparison with the well-characterized tomato Hsfs. These are putative motifs for nuclear import and export and transcriptional activation (AHA motifs). There is intriguing flexibility of size and sequence in certain parts of the otherwise strongly conserved N-terminal half of these Hsfs. We have speculated about possible exon-intron borders in this region in the ancient precursor gene of plant Hsfs, similar to the exon-intron structure of the present mammalian Hsf-encoding genes.

Arabidopsis and the heat stress transcription factor world: how many heat stress transcription factors do we need?

Sequencing of the Arabidopsis genome revealed a unique complexity of the plant heat stress transcription factor (Hsf) family. By structural characteristics and phylogenetic comparison, the 21 representatives are assigned to 3 classes and 14 groups. Particularly striking is the finding of a new class of Hsfs (AtHsfC1) closely related to Hsf1 from rice and to Hsfs identified from frequently found expressed sequence tags of tomato, potato, barley, and soybean. Evidently, this new type of Hsf is well expressed in different plant tissues. Besides the DNA binding and oligomerization domains (HR-A/B region), we identified other functional modules of Arabidopsis Hsfs by sequence comparison with the well-characterized tomato Hsfs. These are putative motifs for nuclear import and export and transcriptional activation (AHA motifs). There is intriguing flexibility of size and sequence in certain parts of the otherwise strongly conserved N-terminal half of these Hsfs. We have speculated about possible exon-intron borders in this region in the ancient precursor gene of plant Hsfs, similar to the exon-intron structure of the present mammalian Hsf-encoding genes.

Arabidopsis and the heat stress transcription factor world: how many heat stress transcription factors do we need?

Sequencing of the Arabidopsis genome revealed a unique complexity of the plant heat stress transcription factor (Hsf) family. By structural characteristics and phylogenetic comparison, the 21 representatives are assigned to 3 classes and 14 groups. Particularly striking is the finding of a new class of Hsfs (AtHsfC1) closely related to Hsf1 from rice and to Hsfs identified from frequently found expressed sequence tags of tomato, potato, barley, and soybean. Evidently, this new type of Hsf is well expressed in different plant tissues. Besides the DNA binding and oligomerization domains (HR-A/B region), we identified other functional modules of Arabidopsis Hsfs by sequence comparison with the well-characterized tomato Hsfs. These are putative motifs for nuclear import and export and transcriptional activation (AHA motifs). There is intriguing flexibility of size and sequence in certain parts of the otherwise strongly conserved N-terminal half of these Hsfs. We have speculated about possible exon-intron borders in this region in the ancient precursor gene of plant Hsfs, similar to the exon-intron structure of the present mammalian Hsf-encoding genes.

Influence of hypothyroid state on 45Ca(2+) influx and sensitivity of rat uterus to nifedipine and diltiazem

The influence of methimazole-induced hypothyroidism on spontaneous rhythmic contractions and Ca2+ channel function of rat uterus was examined. Hypothyroidism significantly reduced the amplitude and frequency of spontaneous rhythmic contractions. Nifedipine (10(-12)-10(-6) M) and diltiazem (10(-9)-10(-4) M) caused concentration-related inhibition of the myogenic responses of the oestrogenised rat uterus obtained from both eu- and hypothyroid rats. However, nifedipine was less potent (IC(50); 5.4 x 10(-9) M; n=6) in hypothyroid rat uterus as compared to euthyroid controls (IC(50): 8.13 x 10(-12) M; n=9) to inhibit the rhythmic contractions. Similarly, diltiazem was less potent (IC(50): 4.57 x 10(-6) M; n=9) to inhibit the uterine spontaneous contractions in hypothyroid than in euthyroid rat uterus (IC(50): 6.4 x 10(-8) M; n=6). A similar decrease in the sensitivity to nifedipine and diltiazem for reversal of K+ (100 mM)-induced tonic contraction was observed in uterus obtained from hypothyroid rats compared to the controls. Both nifedipine and diltiazem were less potent for causing concentration-related inhibition of K+-stimulated 45Ca2+ influx in uterine strips taken from the hypothyroid rats. Thus, the IC(50) values of nifedipine (1.83 x 10(-8) M; n=12) and diltiazem (1.8 x 10(-6) M; n=9) were significantly greater in tissues obtained from hypothyroid rats compared to the controls (IC(50) of nifedipine, 1.15 x 10(-11) M; n=12, diltiazem, 8.1 x 10(-8) M; n=8). Nifedipine-sensitive influx of 45Ca2+ - stimulated either by K+ (100 mM) or Bay k8644 (1,4-dihydro-2,6-dimethyl-5-nitro-4-[2'-(trifluromethyl)phenyl]-3-pyridine carboxylic acid methyl ester) (10(-8) M) was significantly less in uterine strips from hypothyroid rats compared to the controls. The results of the present study suggest that the inhibition of uterine rhythmic contractions may be attributable to a reduction in rat myometrial Ca2+ channel function in the hypothyroid state.

Role of surgery in the management of Graves' disease

Seventy-two patients, 50 women and 22 men, were operated on for Graves' disease. Their median age was 35 years. The indications for surgery included patients with large goitre, relapse after antithyroid drug (ATD) therapy, allergic reactions to ATD, non-compliance and finally an associated nodule with suspicion of carcinoma. Patients were rendered euthyroid with ATD before surgery and were pretreated with Lugol's iodine. Standard subtotal thyroidectomy was performed in 64 patients, total thyroidectomy in 7 patients, and one patient underwent a completion thyroidectomy after an initial subtotal thyroidectomy. The weight of the thyroid remnant on either side was estimated emperically between 3 g and 5 g. There was no postoperative death or thyrotoxic crisis. There was no case of permanent recurrent laryngeal nerve damage or hypoparathyroidism. Eight patients (11.1%) had temporary unilateral vocal cord palsy and 4 patients (5.5%) had temporary hypocalcemia. One patient (1.4%) developed recurrent hyperthyroidism. Postoperative transient hypothyroidism developed in 87.5% cases, all within the first postoperative year. The functional results at 2 years were as follows: Out of 47 cases followed 31 patients (65.9%) became euthyroid while 15 (31.9%) were still hypothyroid and requited long term substitutive treatment. Ophthalmopathy worsened in only one patient. Thyroidectomy has reasonable role in the management of Graves' disease, because the patients have had their diseases rapidly terminated, were hospitalised for an average period of only 3.5 days and have had no permanent functional insult except for hypothyroidism.

Total thyroidectomy for benign thyroid disorders in an endemic region

Total thyroidectomy is increasingly being accepted as a treatment of choice for differentiated thyroid cancer. However, because of presumed increased morbidity associated with this procedure, it is still not considered a viable option for management of benign thyroid disorders. To assess the safety and efficacy of total thyroidectomy for management of benign thyroid disorders, we analyzed our data from 127 total thyroidectomies performed for benign thyroid disorders. Demographic details, biochemical findings, indications for operation, specimen weight, and complications were noted. Among these patients, 52 had a toxic goiter and 75 had a nontoxic goiter. The mean duration of the goiters being present was 6.08 +/- 6.06 years (0.9--26.0 years), and the mean weight of the specimens was 136.88 +/- 120.68 g. The incidence of occult malignancy was 6.3% (n = 8), and those of permanent hypothyroidism and permanent recurrent laryngeal nerve palsy were 1.6% and 0.8%, respectively. Total thyroidectomy should be considered a treatment of choice for multinodular goiter and Graves' disease in a setting of palpable nodule(s) or ophthalmopathy (or both). It is particularly relevant in endemic regions where patients present with a long-standing, large nodular goiter with virtually no normal thyroid tissue. Reoperation for recurrent goiter in such a setting would be fraught with distressing complications.

Occult breast carcinoma: a report of four cases and review of literature

We report four occult carcinoma breast cases in which extensive axillary node metastases was the first manifestation. Upper outer quadrentectomy with axillary dissection was done in three patients while modified radical mastectomy was done in one. Primary tumor could be found in three patients, one had squamous cell carcinoma (SCC) & two had infiltrating duct carcinoma (IDC). However primary tumor was not detected in breast tissue of the fourth patient. Extensive lymph node metastases were found in three out of 14,15 out of 15(SCC), 24 out of 24 and 1 out of three axillary nodes respectively. Results of immunohistochemical staining for estrogen and progesterone receptors on three cases were negative. All patient received postoperative radiotherapy and chemotherapy. We have reviewed the literature and discussed the approach to diagnosis and management in female patients presenting with metastatic carcinoma in the axillary nodes with emphasis on the appropriate pre-treatment evaluation.

Regulation of elongation factor-1alpha expression by growth factors and anti-receptor blocking antibodies

The epidermal growth factor (EGF) family and its receptors regulate normal and cancerous epithelial cell proliferation, a process that could be suppressed by anti-receptor blocking antibodies. Polypeptide elongation factor-1alpha (EF-1alpha) is a multifunctional protein whose levels are positively correlated with the proliferative state of cells. To identify genes, whose expression may be modulated by anti-receptor blocking antibodies, we performed a differential display screening and isolated differentially expressed cDNAs. Isolates from one clone were 100% identical to human EF-1alpha. Both EGF and heregulin-beta1 (HRG) induced EF-1alpha promoter activity and mRNA and protein expression. Growth factor-mediated EF-1alpha expression was effectively blocked by pretreatment with humanized anti-EGF receptor antibody C225 or anti-human epidermal growth factor receptor-2 (HER2) antibody herceptin. Mutants and pharmacological inhibitors of p38(MAPK) and MEK, but not phosphatidylinositol 3-kinase, suppressed both constitutive and HRG-induced stimulation of EF-1alpha promoter activity in MCF-7 cells. Deletion analysis of the promoter suggested the requirement of the -393 to -204 region for growth factor-mediated transcription of EF-1alpha. Fine mapping and point mutation studies revealed a role of the SP1 site in the observed HRG-mediated regulation of the EF-1alpha promoter. In addition, we also provide new evidence to suggest that HRG stimulation of the EF-1alpha promoter involves increased physical interactions with acetylated histone H3 and histone H4. These results suggest that regulation of EF-1alpha expression by extracellular signals that function through human EGF receptor family members that are widely deregulated in human cancers and that growth factor regulation of EF-1alpha expression involve histone acetylation.

Detection and analysis of chromosomal arsenic resistance in Pseudomonas fluorescens strain MSP3

Pseudomonas fluorescens MSP3 isolated from sea water was resistant to arsenate. This bacterium harbored no plasmids, indicating that arsenic resistance was chromosomally encoded. The chromosomal DNA from MSP3 when transformed onto Escherichia coli DH5alpha using pBluescript exhibited resistance to sodium arsenate and sodium arsenite. Three clones MSA1, MSA2, and MSI3 containing the ars genes were obtained and further subcloning resulted in three fragments of size 2.2, 2.6, and 2.1 kb for pMSA11, pMSA12, and pMSI13, respectively, which contained the genes arsRBC of the arsenic operon. An efflux mechanism of detoxification was observed which was ATP dependent. The resistance mechanism was encoded from a single operon which consisted of an arsenite inducible repressor that regulates the expression of arsenate reductase (ars C) and inner membrane associated arsenite export system encoded by ars B. The chromosomal operon was cloned, sequenced, and found to consist of three cistrons, named as ars R, ars B, and ars C. Southern hybridization and mating experiments confirmed the functioning of the ars genes in the operon, thereby conferring increased resistance to sodium arsenate and sodium arsenite.

Squamous cell carcinoma of thyroid gland

We present the clinical manifestation, management and outcome in two cases of squamous cell cancer arising in the thyroid gland which is a rare entity. Both cases had advanced disease invading adjacent structures. At the followup of three to six months, one patient developed recurrence and died.

Functioning adrenal tumours in children and adolescents: an institutional experience

BACKGROUND

The purpose of the present paper was to carry out an audit of clinicopathological profile and treatment outcome in 13 children with functioning adrenal tumours.

METHODS

The medical records of 13 children with functioning adrenal tumours who were managed between June 1990 and January 1999 were reviewed. Demographic data, clinical features, biochemical and localization studies, operative details and follow-up records were studied. Children with neuroblastoma were excluded.

RESULTS

The mean age was 7.4 +/- 5.3 years. Seven patients had Cushing's syndrome (CS), two patients had virilizing tumours, three patients had phaeochromocytoma (PCC) and one patient had Conn's syndrome. All patients (except one child with CS) were treated surgically. Two children with adrenocortical carcinoma (ACCa) died during the perioperative period. Histopathological diagnosis was adrenal cortical adenoma (ACAd) in four patients, ACCa in five patients and PCC in three patients. Two ACCa patients died of metastases at 12 and 14 months, respectively, while the third is alive and well at 30 months. Children with ACAd are alive and well at 91, 56, 32 and 27 months postoperatively. Children with PCC are free of disease (normal urinary metanephrines) at 63, 18 and 8 months after surgery but require antihypertensive drugs in low doses.

CONCLUSION

The outcome of surgery is good in cases of ACAd and PCC. Although outcome is poor in ACCa, surgery remains the mainstay of treatment and offers good palliation.

Transcriptional repression of oestrogen receptor by metastasis-associated protein 1 corepressor

Activation of the heregulin/HER2 pathway in oestrogen receptor (ER)-positive breast-cancer cells leads to suppression of oestrogen-receptor element (ERE)-driven transcription and disruption of oestradiol responsiveness, and thus contributes to progression of tumours to more invasive phenotypes. Here we report the identification of metastatic-associated protein 1 (MTA1), a component of histone deacetylase (HDAC) and nucleosome-remodelling complexes, as a gene product induced by heregulin-beta1 (HRG). Stimulation of cells with HRG is accompanied by suppression of histone acetylation and enhancement of deacetylase activity. MTA1 is also a potent corepressor of ERE transcription, as it blocks the ability of oestradiol to stimulate ER-mediated transcription. The histone-deacetylase inhibitor trichostatin A blocks MTA1-mediated repression of ERE transcription. Furthermore, MTA1 directly interacts with histone deacetylase-1 and -2 and with the activation domain of ER-alpha. Overexpression of MTA1 in breast-cancer cells is accompanied by enhancement of the ability of cells to invade and to grow in an anchorage-independent manner. HRG also promotes interaction of MTA1 with endogenous ER and association of MTA1 or HDAC with ERE-responsive target-gene promoters in vivo. These results identify ER-mediated transcription as a nuclear target of MTA1 and indicate that HDAC complexes associated with the MTA1 corepressor may mediate ER transcriptional repression by HRG.

Tuberculous granulomatous inflammation associated with adenoma of parathyroid gland manifesting as primary hyperparathyroidism

A 36-year-old female presented with generalized bone pain, muscular weakness and enlarged cervical lymph nodes. The biochemical findings and skeletal survey was suggestive of primary hyperparathyroidism (PHPT). CT of neck and thorax showed enlarged multiple lymph nodes in the cervical and superior mediastinal region. With a diagnosis of PHPT she underwent cervical exploration and excision of enlarged right inferior parathyroid gland along with biopsy of nodes were done. Histopathology revealed the features of right parathyroid adenoma with few foci of epithelioid granuloma and granulomatous lymphadenitis. AFB smear and culture sensitivity was negative. A positive PCR for Mycobacterium tuberculosis of the homogenates of parathyroid tumor confirmed tuberculous inflammation within the parathyroid adenoma. To the best of our knowledge this is the first reported case of parathyroid adenoma associated with tuberculous pathology in a case of PHPT.

Isolated Pneumocystis carinii infection of adrenal glands causing Addison's disease in a non-immunocompromised adult

Pneumocystis carinii is primarily an opportunistic pathogen infecting patients with AIDS and other immunocompromised patients, and ordinarily does not affect immunocompetent persons. We report isolated P. carinii infection of bilateral adrenal glands in a non-immunocompromised adult male, leading to fatal Addisonian crisis. Diagnosis of P. carinii was established on the basis of cytopathology and microbiological tests, using conventional staining techniques and direct immunofluorescence on ultrasound-guided fine needle aspirates and trucut needle biopsy specimen from adrenal glands. P. carinii pneumonia and other fungal infections of the adrenal glands were excluded by appropriate tests. Absence of HIV infection was established by negative ELISA for HIV I and II antibodies and Western blot analysis at the time of presentation and 45 d later. Normal blood total leukocyte and CD4 lymphocyte counts and IgG and IgA levels confirmed the immunocompetent status of the patient. The patient improved with anti-Pneumocystis treatment and corticosteroid replacement, but succumbed to an episode of Addisonian crisis triggered by a diarrheal illness.

Growth of Steptomyces hygroscopicus in rotating-wall bioreactor under simulated microgravity inhibits rapamycin production

Growth of Streptomyces hygroscopicus under conditions of simulated microgravity in a rotating-wall bioreactor resulted in a pellet form of growth, lowered dry cell weight, and inhibition of rapamycin production. With the addition of Teflon beads to the bioreactor, growth became much less pelleted, dry cell weight increased but rapamycin production was still markedly inhibited. Growth under simulated microgravity favored extracellular production of rapamycin, in contrast to a greater percentage of cell-bound rapamycin observed under normal gravity conditions.

Relief from glucose interference in microcin B17 biosynthesis by growth in a rotating-wall bioreactor

Glucose interference in production of microcin B17 by Escherichia coli ZK650 was decreased sevenfold by growth in a ground-based rotating-wall bioreactor operated in the simulated microgravity mode as compared with growth in flasks. When cells were grown in the bioreactor in the normal gravity mode, relief from glucose interference was even more dramatic, amounting to a decrease in glucose interference of over 100-fold.

Electronic spectra of adenine and 2-aminopurine: an ab initio study of energy level diagrams of different tautomers in gas phase and aqueous solution

Ground and lowest two singlet excited state geometries of four tautomeric forms (N9H, N7H, N3H and N1H) of each of adenine and 2-aminopurine (2AP) were optimized using an ab initio approach employing a mixed basis set (6-311 + G* on the nitrogen atom of the amino group and 4-31G basis set on the other atoms). Excited states were generated employing configuration interaction involving single electron excitations (CIS). Subsequently, the different species were solvated in water employing the self-consistent reaction field (SCRF) approach along with the corresponding gas phase optimized geometries. Thus the observed absorption and fluorescence spectra of adenine and 2AP have been explained successfully. It is concluded that both the N9H and N7H forms of 2AP would contribute to absorption and fluorescence spectra. Further, the fluorescence of 2AP would be absorbed by its cation in which both the N9 and N7 atoms are protonated, the fluorescence of which can have an anti-Stokes component. Among the different tautomers of adenine, the N9H form would be present dominantly in the ground state in aqueous solutions but the N7H form would be produced by energy transfer and subsequent fluorescence. The N3H form of adenine appears to be responsible for the observed absorption near 300 nm by its solutions intermittently exposed to ultraviolet radiation. The rings of the different species related to 2AP and adenine remain almost planar in the pi-pi* and n-pi* singlet excited states as in the ground state. The pyramidal character of the amino group is usually less in the pi-pi* excited states than that in the corresponding ground or n-pi* excited states. Molecular electrostatic potential (MEP) maps of the molecules provide useful clues regarding phototautomerism.

Endothelium-dependent relaxation of rat aorta and main pulmonary artery by the phytoestrogens genistein and daidzein

OBJECTIVE

The dietary phytoestrogens genistein and daidzein have been shown to relax agonist-preconstricted arteries in vitro; the mechanisms of relaxation remain incompletely understood. This study aimed to determine whether the relaxation of phenylephrine (PE)-constricted rat aorta and main pulmonary artery by genistein and daidzein was endothelium-dependent.

METHODS

Effects of endothelial-denudation, and pretreatment with with 100 microM L-N(G)-nitroarginine methyl ester (L-NAME) and/or 10 microM indomethacin on relaxation of PE (1 microM)-preconstricted contractures by genistein (1-100 microM) and daidzein (3-100 microM) were assessed by measuring isometric force development by rat arterial rings. The effect of L-NAME on relaxation to 17beta-estradiol (10 microM) was also measured in aorta.

RESULTS AND CONCLUSIONS

Genistein and daidzein caused concentration-dependent relaxation of aorta rings preconstricted with PE (1 microM). The IC50 values were 5.7 microM (n=8, 95% confidence limits 4.3-7.7 microM) and 36.7 microM (n=12, 95% confidence limits 25.7-44.1 microM), respectively. Removal of the endothelium and pretreatment with L-NAME (100 microM) significantly inhibited relaxation at 3, 10 and 30 microM genistein and 10 and 30 microM daidzein. The contracture evoked in rat aorta by depolarization with 75 mM K+ solution was similarly relaxed by genistein in a partially endothelium-dependent manner. 17Beta-estradiol (10 microM) caused a 48.7+/-5.0% (n=11) relaxation of the PE contracture, which was significantly reduced to 25.1+/-5.3% (n=7) by L-NAME. Relaxations brought about by 17beta-estradiol, genistein, and daidzein were not significantly affected by the genomic estrogen receptor antagonist ICI 182,780 (10 microM). Similar endothelium-dependent effects of genistein were observed in the main pulmonary artery. The results show that the relaxation of these rat arteries by concentrations of genistein and daidzein which overlap those present in human plasma after ingestion of soybean-containing meals is largely endothelium dependent.

Avirulent mutants of Macrophomina phaseolina and Aspergillus fumigatus initiate infection in Phaseolus mungo in the presence of phaseolinone; levamisole gives protection

To evaluate the role of phaseolinone, a phytotoxin produced by Macrophomina phaseolina, in disease initiation, three nontoxigenic avirulent mutants of the fungus were generated by UV-mutagenesis. Two of them were able to initiate infection in germinating Phaseolus mungo seeds only in the presence of phaseolinone. The minimum dose of phaseoli-none required for infection in 30% seedlings was 2 5 mg/ml. A human pathogen, Aspergillus fumigatus was also able to infect germinating seeds of P. mungo in the presence of 5 mg/ml concentration of phaseolinone. Phaseolinone seemed to facilitate infection by A. fumigatus, which is not normally phytopathogenic, by reducing the immunity of germinating seedlings in a nonspecific way. Levamisole, a non-specific immunopotentiator gave protection against infection induced by A. fumigatus at an optimum dose of 50 mg/ml. Sodium malonate prevented the effects of levamisole.