Characterization of two distinct P2Y receptors in human tracheal gland cells

Human submucosal tracheal glands are now believed to play a major role in the physiopathology of cystic fibrosis, a genetic disease in which ATP is used as a therapeutic agent. However, actions of ATP on tracheal gland cells are poorly known. ATP-binding characteristics, and ATP-induced formation of cAMP were investigated in a cell line (MM39) of human tracheal gland cells. The binding of a radiolabelled non-hydrolysable analogue of ATP Adenosine-5'-[35S]thiotriphosphate: [35S]ATP[gammaS] was rapid (within 30 min at 4 degrees C), stable and reversible. Scatchard analysis revealed two classes of [35S]ATP[gammaS]-binding sites. Low-affinity binding sites had a Kd1 of 20 +/- 5 microM (Bmax = 150 nmol/10(6) cells) and the high-affinity binding sites had a Kd2 of 2.5 +/- 0.2 microM (Bmax = 52 nmol/10(6) cells). Competition experiments showed competition with ATP, ADP and 2-methylthio-ATP but no competition with UTP, AMP and adenosine. UTP stimulates protein secretion as well as it induced [Ca2+]i mobilization but did not affect the intracellular cAMP levels. ATP also caused induced [Ca2+]i mobilization and protein secretion but also caused an increase in cyclicAMP content of the cells, reaching a maximum after 1 min. ATP-induced cAMP formation was concentration dependent and inhibited by the P2-antagonist suramin. Reverse-transcription-PCR amplification revealed the presence of the transcripts of both the P2Y2 and the UTP-specific P2Y4 receptors. In conclusion, P2Y2 receptors, UTP-P2Y4 receptors and unidentified ATP-specific receptors seem to be present in MM39 cells which appear to be coupled differently to intracellular second-messenger systems.

Resolution of hydatid liver cyst by spontaneous rupture into the biliary tract

Among the complications of hydatid liver disease, spontaneous cyst rupture into the biliary tract is unusual, occurring in 3.2-17% of cases. Its endoscopic management has been reported rarely, and corresponding complete photodocumentation is unique. Such a case is described and comprehensively illustrated in a 48-year-old immunocompromised man, presenting with upper abdominal pain, obstructive jaundice, and fever. Impaction of hydatid material into the common bile duct and the papilla of Vater was relieved endoscopically, and the patient was consecutively treated with two courses of mebendazole. This management resulted in complete clinical resolution of hepatic hydatosis after 8 months of follow-up. Complications of overt cyst perforation may be allergic, obstructive, secondary infectious, or metastatic. Ultrasound and computed tomography are complementary tools for diagnosis of hepatic echinococcosis, with endoscopic retrograde cholangiography being the "gold standard" in confirming rupture into the biliary system. Laboratory results are usually non-specific. While surgical excision is the treatment of choice, selected patients may primarily be managed endoscopically, followed by anthelminthic therapy.

Preoperative chemotherapy for congenital hemangiopericytoma and a review of the literature

PURPOSE

Malignant hemangiopericytoma is an uncommon tumor in the pediatric age group. A case of congenital hemangiopericytoma is presented with a review of the literature.

PATIENTS AND METHODS

A 2-month-old boy presented at birth with an enlarging posterior neck mass. Subsequent histopathologic studies showed findings consistent with hemangiopericytoma. Imaging studies demonstrated an extensive, infiltrative, vascular lesion not readily amenable to surgical resection. A pulmonary metastatic lesion was present.

RESULTS

Combined treatment using vincristine, doxorubicin, and cyclophosphamide given preoperatively resulted in a significant decrease in size of the primary tumor, allowing for resection without complication and resolution of the metastatic lesion.

CONCLUSION

Preoperative chemotherapy may have a significant role in the management of infants with malignant hemangiopericytoma.

Identification of native complexes containing the yeast coactivator/repressor proteins NGG1/ADA3 and ADA2

NGG1p/ADA3p and ADA2p are dual function regulators that stimulate or inhibit a set of yeast transcriptional activator proteins. In vitro, NGG1p and ADA2p associate in a complex that also contains GCN5p (Horiuchi, J., Silverman, N., Marcus, G. A., and Guarente, L. (1995) Mol. Cell. Biol. 15, 1203-1209). We have found that NGG1p and ADA2p are coimmunoprecipitated from yeast whole cell extracts. In fact, <2% of cellular ADA2p was not associated with NGG1p. Also in agreement with their association in vivo, the stability of ADA2p and NGG1p depended on the presence of each other. In addition, three NGG1p- and ADA2p-containing peak fractions were resolved by Q-Sepharose Fast Flow ion-exchange chromatography of whole cell extract. The presence of another high molecular mass complex was supported by the separation of one of the NGG1p- and ADA2p-containing peak fractions by gel-filtration chromatography. Together, the combination of ion-exchange and gel-filtration chromatography suggests a total of four complexes, two with sizes of >2 MDa and single complexes of approximately 900 and 200 kDa. At least one of these complexes was found to associate with the TATA-binding protein (TBP) since TBP was present in immunoprecipitates with NGG1p. The association of TBP with the ADA proteins required amino acids 274-307 of NGG1p, a region of NGG1p required for activity. This supports a role for NGG1p in the interaction with TBP and suggests that the interaction with TBP is functionally relevant.

Toxicity associated with high-dose cytosine arabinoside and total body irradiation as conditioning for allogeneic bone marrow transplantation

Seventy-three patients with hematological cancers undergoing allogeneic bone marrow transplantation (BMT) were evaluated for event-free survival (EFS) and toxicity. All received 36 g/m2 cytosine arabinoside (HDA) and 1200 cGy fractionated total body irradiation (TBI). We assessed the association of EFS and toxicities with the following risk factors; age, gender, diagnosis, initial relapse risk and patient-donor histocompatibility. The EFS probability is 33% at 800 days post-BMT. Twenty-six patients (36%) died of toxicity within 100 days and 14 (19%) have relapsed. EFS was inversely associated with age (P < 0.0001) and initial relapse risk (P = 0.007). The risk of pulmonary (P = 0.023) and hepatic toxicity (P = 0.011) increased with age. Diagnosis other than acute lymphoblastic leukemia (ALL) was a risk factor (P = 0.015) for graft-versus-host disease (GVHD); and fewer ALL patients died from toxicity (P = 0.014). The probability of sepsis within 100 days post-BMT correlated (P = 0.007) with initial relapse risk. We conclude: (1) the lower EFS and greater pulmonary and hepatic toxicity associated with increasing age indicate a need for less toxic regimens that maintain high antileukemic efficacy for older patients; (2) the high GVHD and sepsis rates seen in certain categories of patients indicate a need for careful definition of eligibility criteria for this still highly toxic treatment.

Transcriptional activation by yeast PDR1p is inhibited by its association with NGG1p/ADA3p

NGG1p/ADA3p forms a coactivator/repressor complex (ADA complex) in association with at least two other yeast proteins, ADA2p and GCN5p, that is involved in regulating transcriptional activator proteins including GAL4p and GCN4p. Using a two-hybrid analysis, we found that the carboxyl-terminal transcriptional activation domain of PDR1p, the primary regulatory protein involved in yeast pleiotropic drug resistance, interacts with the amino-terminal 373 amino acids of NGG1p (NGG1p1-373). This interaction was confirmed by coimmunoprecipitation of epitope-tagged derivatives of NGG1p and PDR1p from crude extracts. An overlapping region of the related transcriptional activator PDR3p was also found to interact with NGG1p. Amino acids 274-307 of NGG1p were required for interaction with PDR1p. This same region is required for inhibition of transcriptional activation by GAL4p. The association between NGG1p1-373 and PDR1p may be indirect, possibly mediated by the ADA complex since the two-hybrid interaction required the presence of full-length NGG1. A partial requirement for ADA2 was also found. This suggests that an additional component of the ADA complex, regulated by ADA2p, may mediate the interaction. Transcriptional activation by a GAL4p DNA binding domain fusion of PDR1p was enhanced in ngg1 and ada2 disruption strains. Similar to its action on GAL4p, the ADA complex acts to inhibit the activation domain of PDR1p.

Structure/functional properties of the yeast dual regulator protein NGG1 that are required for glucose repression

NGG1p/ADA3p is a yeast dual function regulator required for the complete glucose repression of GAL4p-activated genes (Brandl, C. J., Furlanetto, A. M., Martens, J. A., and Hamilton, K. S. (1993) EMBO J. 12, 5255-5265). Evidence for a direct role for NGG1p in regulating activator function is supported by the finding that NGG1p is also required for transcriptional activation by GAL4p-VPl6 and LexA-GCN4p (Pina, B., Berger, S. L., Marcus, G. A., Silverman, N., Agapite, J., and Guarente, L. (1993) Mol. Cell. Biol. 13, 5981-5989). By analyzing deletion derivatives of the 702-amino acid protein, we identified a region essential for glucose repression within residues 274-373. Essential sequences were further localized to a segment rich in Phe residues that is predicted to be an amphipathic alpha helix. As well as finding mutations within this region that reduced glucose repression, we identified mutations that made NGG1p a better repressor. In addition, NGG1p probably represses GAL4p activity as part of a complex containing ADA2p because single and double disruptions of ngg1 and ada2 had comparable effects on glucose repression. We also localized a transcriptional activation domain within the amino-terminal amino acids of NGG1p that is proximal or overlapping the region required for glucose repression. Activation by GAL4p-NGG1p(1-373) requires ADA2p; however, activation by GAL4p-NGG1p(1-308), is ADA2p-independent. This suggests that a site required for ADA2p interaction lies between amino acids 308 and 373 and that ADA2p has a regulatory role in activation by GAL4p-NGG1p(1-373).

[Percutaneous treatment of tumors of the upper urinary tract]

In our Institution, 23 patients were selected for percutaneous resection of tumors of the upper urinary tract. Two patients underwent a second procedure: the first for ipsilateral recur and the second for an heterolateral tumor. Among these 23 patients, 11 presented a benign tumor, 9 were treated for a transitional carcinoma of whom 2 invasive state. Both underwent a nephro-ureterectomy. For the 7 superficial transitional carcinomas, the mean follow-up period is 30.4 months. The ipsilateral local recurrencee is 14.3% (1/7), and concern a poorly differentiated tumor (G III). The advantage of the endoscopic techniques to explore and treat the upper urinary tract tumors is double. With these techniques, we can diagnose and treat adequately benign tumors which don't justify radical surgery. In the case of transitional tumors, the percutaneous way is an acceptable method of management when it appears better to avoid a radical treatment (solitary kidney, bilateral synchronous tumors, impairment of total renal function, general injuries). However, it must be performed only in selected cases, and patients should be carefully selected.

Acid-base status and intracellular pH regulation in lymphocytes from rats with genetic hypertension

This article reviews work from this laboratory dealing with acid-base status and intracellular pH (pHi) regulation in rat genetic models of hypertension. With freshly isolated thymic lymphocytes, pHi and its regulation were examined in the spontaneously hypertensive rat (SHR). In this rat model, pHi was found to be reduced as compared with that of lymphocytes from normotensive Wistar-Kyoto (WKY) rats. The activity of the Na+/H+ antiporter assessed after stimulation by acute cell acidification was similar in lymphocytes from SHR and WKY rats both in the nominal absence of HCO3- and in media containing HCO3- (22 mM). The kinetic properties of the Na+/H+ antiporter, examined as a function of pHi with the Hill kinetic model, revealed no significant differences between lymphocytes from SHR and WKY rats. The kinetic properties of the Na(+)-dependent and Na(+)-independent Cl(-)-HCO3- exchangers, examined as a function of external Cl-, were also virtually identical in lymphocytes from SHR and WKY rats. Unlike the Na(+)-H+ exchanger and the Na(+)-independent Cl(-)-HCO3- exchanger, which had their highest activities at extremes of pHi (low pHi, Na(+)-H+ exchanger; high pHi, Na(+)-independent Cl(-)-HCO3- exchanger), the Na(+)-dependent Cl(-)-HCO3- exchanger had its maximal activity near steady-state pHi. In Dahl/Rapp salt-sensitive rats with hypertension, the pHi of thymic lymphocytes was also reduced as compared with that of normotensive salt-resistant animals. In this model, renal net acid excretion in salt-sensitive rats was augmented as compared with that of salt-resistant rats. The increase in renal acid excretion was due to an increase in both ammonium and titratable acid excretion and was observed while animals were placed on high, normal and low salt diets. The findings of intracellular acidosis and enhanced renal acid excretion suggest that cellular acid overproduction is augmented in salt-sensitive hypertension.

Single dose aprotinin in routine cardiac surgery

Evidence exists that the serine protease inhibitor, aprotinin, when used in high dosage, can reduce the bleeding associated with cardiopulmonary bypass. This high dosage is particularly effective in patients at increased risk for bleeding. Less convincing information is available for regimens that use a lower dose and its place in routine cardiac surgery has not been fully resolved. Some studies have shown significant benefit from a single dose added to the cardio-pulmonary bypass prime and we re-examined this alternative. In a randomized, prospective, double-blinded study, we compared this single dose method with placebo in a low risk adults undergoing a first procedure. Benefit was considered established if a significant reduction in blood loss or the use of transfused blood products was seen. We found a significant reduction in red cell transfusion but no improvement in blood loss or blood component transfusion in the treated group. This included patients maintained on aspirin as well as those not receiving aspirin. Aspirin significantly increased blood loss in both control and treatment groups and the usage of blood products in the treatment group. Aprotinin in this low, single dosage was not confirmed as an effective means of improving hemostasis following CPB in routine cardiac surgery.

Renal acid excretion and intracellular pH in salt-sensitive genetic hypertension

Acid-base status and renal acid excretion were studied in the Dahl/Rapp salt-sensitive (S) rat and its genetically salt-resistant counterpart (R). S rats developed hypertension while on a very high salt diet (8%) and while on a more physiological salt diet (1%) and remained normotensive while on a very low salt diet (0.08%). Under the high salt diet, intracellular pH measured in freshly isolated thymic lymphocytes using 2',7'-bis (carboxyethyl)-5 (6)-carboxyfluorescein acetomethyl ester, a pH-sensitive dye, was lower in S than in R rats both when measured in the presence of HCO3/CO2 (7.32 +/- 0.02 vs. 7.38 +/- 0.02, respectively, P < 0.05) and in its absence (7.18 +/- 0.04 vs. 7.27 +/- 0.02, respectively, P < 0.05). Under the high salt diet, net acid excretion was higher in S than R rats (1,777 +/- 111 vs. 1,017 +/- 73 muEq/24 h per 100 g body wt, respectively, P < 0.001), and this difference was due to higher rates of both titratable acid and ammonium excretion. Directionally similar differences in intracellular pH and net acid excretion between S and R rats were also observed in salt-restricted animals. In S and R rats placed on a normal salt intake (1%) and strictly pair-fed to control food intake as a determinant of dietary acid, net acid excretion was also higher in S than in R rats (562 +/- 27 vs. 329 +/- 21 muEq/24 h per 100 g, respectively, P < 0.01). No significant difference in either blood pH or bicarbonate levels were found between S and R rats on either the 0.08%, 1%, or 8% salt diets. We conclude that renal acid excretion is augmented in the salt-sensitive Dahl/Rapp rat. Enhanced renal acid excretion may be a marker of increased acid production by cells from subjects with salt-sensitive hypertension.

The sonographically thick placenta: a predictor of increased perinatal morbidity and mortality

In order to determine the prevalence and significance of sonographically thick placentas, we reviewed the computerized records of 18 827 viable, singleton pregnancies. Of these, 116 (0.6%) had thick placentas diagnosed by ultrasound examination. Perinatal mortality was markedly increased among pregnancies with thick placentas (odds ratio = 13.1, 95% confidence limits (CL) = 8.3-20.8), accounting for 6.2%; of the total. The rates of abruptio placentae (odds ratio = 2.9, CL = 1.1-8.1), neonatal intensive care unit admissions (odds ratio = 4.6, CL = 3.1-6.9) and anomalies (odds ratio = 8.4, CL = 4.9-14.4) were also significantly increased among the thick placenta cohort compared to controls. The 106 liveborn neonates with thick placentas had lower Apgar scores, were delivered at an earlier gestational age, and weighed less than controls. Anomalies, hydrops fetalis and abruptio placentae complicated 16 of the 24 cases of perinatal mortalities. Sonographically thick placentas should alert the clinician to the possibility of compromised perinatal outcome.

Glucose-6-phosphate dehydrogenase deficiency and sulfadimidin acetylation phenotypes in Egyptian oases

Screening of 1315 males from two Egyptian oases for glucose-6-phosphate dehydrogenase deficiency (G-6PD) found an incidence of 5.9%. The rate of acetylation of sulfadimidin was also studied, and a bimodal distribution was found with 73% rapid acetylators. There is a correlation between high frequency of G-6PD deficiency and high frequency of slow acetylation rate.

"Downhill" oesophagus varices: a clue to a serious disease

Downhill oesophagus varices are rarely observed. In this report a patient is described with downhill oesophagus varices in the absence of the vena cava superior syndrome. The observation of these varices was the clue to the diagnosis of a serious disease: a malignant thymoma.

Cytosolic calcium in T lymphocytes from the spontaneously hypertensive rat

To gain further insight into the possible generalized nature of intracellular calcium-related alterations in hypertension we measured free cytosolic calcium (iCa2+) in lymphocytes obtained from the spleen and the blood of the spontaneously hypertensive rat (SHR) and age-matched normotensive Wistar-Kyoto (WKY) rats. By monitoring Fura-2 fluorescence at an excitation wavelength of 340 nm and an emission wavelength of 510 nm we estimated; Ca2+. In peripheral lymphocytes from the SHR iCa2+ was increased as compared to those from WKY rats (146 +/- 14 and 112 +/- 6.0 nm, respectively, P less than .025). In contrast, in lymphocytes obtained from the spleen, iCa2+ was not different between SHR and WKY rats (93 +/- 7.0 and 96 +/- 8.0 nm, respectively). When spleen cells were subjected to selective B lymphocyte depletion to generate a preparation of predominantly T lymphocytes, iCa2+ was found to be higher in SHR than in WKY rats (149 +/- 23 and 89 +/- 12 nm, respectively, P less than .05). The finding that iCa2+ is elevated in peripheral lymphocytes and spleen cells subjected to B cell depletion but not in untreated spleen cells indicates that T, but not B, lymphocytes have increased iCa2+ in the SHR. This observation may be related to existing evidence that T lymphocyte function is impaired in the SHR. An increase in iCa2+ is not a phenomenon generalized to all cells of this model of genetic hypertension.

Reduced intracellular pH in lymphocytes from the spontaneously hypertensive rat

This study was designed to determine the cytoplasmic pH (pHi) profile of lymphocytes from a rat model of genetic hypertension that is well suited for study before and after the development of spontaneous hypertension. For this purpose, pHi was measured in thymic lymphocytes obtained from spontaneously hypertensive rats (SHR) and from age-matched Wistar-Kyoto (WKY) control rats using 2',7'-bis carboxyethyl-5,6-carboxyfluorescein (BCECF), a pH-sensitive fluorescence probe. At the age of 16-20 weeks, pHi of lymphocytes suspended in a HCO3-free HEPES-buffered solution, was markedly lower in the SHR than in the WKY rats (7.07 +/- 0.02, n = 16 and 7.22 +/- 0.01, n = 15, respectively, p less than 0.001), whereas systolic blood pressure was higher in SHR than in WKY rats (175 +/- 5.0 and 105 +/- 3.0 mm Hg, respectively, p less than 0.001). In rats less than 5 weeks of age, pHi was also lower in SHR than in WKY rat lymphocytes (7.12 +/- 0.04, n = 11 and 7.23 +/- 0.04, n = 11, respectively, p less than 0.05), although at this age systolic blood pressure was not different between the two groups (87 +/- 4.0 and 85 +/- 3.0 mm Hg, respectively). In lymphocytes suspended in a more physiological HCO3/CO2-buffered solution, pHi was again lower in the adult SHR than in the WKY rat (7.18 +/- 0.02, n = 16 and 7.31 +/- 0.02, n = 16, respectively, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Antiparietal cell antibodies in gastritis associated with chronic liver diseases

Thirty patients with gastritis associated with chronic liver disease and ten normal controls were the subject of this study. Pathologically about 18 were diagnosed as chronic atrophic gastritis, 10 as chronic superficial gastritis, 1 as gastric atrophy and 1 as hypertrophic gastritis. Parietal cell antibodies (PCA) were detected (IFA) in 2 cases with no significant relation.

Urinary C-peptide in the neonate correlates both to maternal glucose tolerance and to fetal size at birth

In 18 women with gestational diabetes the variables of an oral glucose tolerance test (fasting and 2-hour blood glucose values and area under the blood glucose curve) performed in the last trimester of pregnancy correlated significantly with the urinary C-peptide excretion during the first 12 hours of the life (r = 0.47, 0.71, and 0.60, respectively). In a combined group with 28 type II pregnant diabetic women there was also a significant correlation between the urinary C-peptide excretion of the infants and their skinfold. Assay of the urinary C-peptide excretion of the neonate, reflecting its insulin production, seems to be a sensitive parameter to study the influence of the maternal carbohydrate metabolism in the offspring.

Effect of Copper T intrauterine device on cervico-vaginal flora

The effect of the Copper T intrauterine device (IUD) insertion on vaginal and cervical flora was studied in thirty cases. The vaginal and cervical cultures showed a significant increase (P less than 0.01) in some of the anaerobic bacteria. Some of the aerobic organisms showed a statistically significant increase in the cervical cultures (P less than 0.01). Strict asepsis during insertion of the device is recommended.