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Biomedical subjects

A Cano

Publications and source records attributed to A Cano.

At least 127 records · Page 7Linked to original sources
PubMed1995

Acid incubation increases NHE-3 mRNA abundance in OKP cells.

With the use of degenerate primers based on conserved amino acid sequences in human, rat, and rabbit Na/H exchanger-3 (NHE-3), a polymerase chain reaction product was obtained from reverse-transcribed OKP (a clonal opossum kidney cell line) mRNA and used to screen an OKP cDNA library. The clone obtained predicted an amino acid sequence that was 86% identical to rat NHE-3, 33% to NHE-1, 35% to NHE-2, and 30% to NHE-4. Expression of the corresponding cRNA in Xenopus oocytes induced 22Na uptake with ethylisopropylamiloride. (EIPA) resistance similar to that of the OKP Na/H antiporter. On RNA blot, the cDNA labeled a 9.5-kb transcript whose abundance was increased 2.2-fold by 24-h incubation of OKP cells at pH 7.0 and 2.5-fold by 24-h incubation at pH 6.8. The acid-induced increase in NHE-3 mRNA was detectable at 12 h and increased further at 24 h. Incubation in acid media caused an increase in EIPA-resistant Na/H antiporter activity that preceded the increase in NHE-3 mRNA. In summary, OKP cells express an NHE-3 transcript that encodes an EIPA-resistant Na/H antiporter and is chronically regulated by acid.

Acids↗
PubMed1995

Anomalous expression of P-cadherin in breast carcinoma. Correlation with E-cadherin expression and pathological features.

Previous studies on the cell-cell adhesion molecules P- and E-cadherin have shown that P-cadherin is not expressed in breast cancer. In contrast, the expression of E-cadherin is a normal event in these tumors, but a reduction in the levels of this molecule in neoplastic cells is associated with the histological type, high histological grade, greater tumor size, and metastasis. The expression pattern of P- and E-cadherin were immunohistochemically studied in tissue sections from normal breast tissue, benign breast lesions, and 57 infiltrating breast carcinomas. Cadherin expression was analyzed in parallel with pathological features and the immunohistochemical expression of estrogen and progesterone receptors in breast carcinomas. P-cadherin was detected in the myoepithelial cells and E-cadherin in luminal epithelial cells from normal breast and benign breast lesions. P-cadherin expression was detected in 9 of 45 cases (20%) of infiltrating ductal carcinomas of no special type; none of the special histological types that were analyzed (7 infiltrating lobular carcinomas, 3 colloid carcinomas, and 2 infiltrating papillary carcinomas) expressed P-cadherin. In infiltrating ductal carcinomas, P-cadherin expression correlated significantly with a reduction in E-cadherin expression, histological grade (all cases were grade III tumors), and hormone receptor content (8 of 9 cases were estrogen and progesterone receptor negative). Although E-cadherin was not found in the 7 infiltrating lobular carcinomas, it was present in the remaining histological types and was preserved in 15 infiltrating ductal and 3 colloid and 2 papillary carcinomas and was reduced in 30 infiltrating ductal carcinomas. In addition, a reduction in E-cadherin expression was significantly associated with high histological grade and a lack of steroid hormone receptors in infiltrating ductal carcinomas. No apparent relationship was found between P- and E-cadherin expression and tumor size and axillary lymph node metastasis. The distinct patterns of P- and E-cadherin expression observed in this study strongly suggest a differential role for these cadherins in human breast carcinogenesis.

Actins↗
PubMed1995

[Spinal cord ischemia indicating aneurysm of the abdominal aorta. Report of three cases].

We report 3 cases of dorsal ischemic myelopathy indicative of aneurysm of the abdominal aorta. In 2 cases the aneurysm was dissecting and in all patients medullary symptoms were preceded by sudden lumbar or abdominal pain. Neurological symptoms were slightly different in each case. One patient experienced 3 episodes of acute paraparesis and rapid regression evoking transitory medullary ischemic accidents (intermittent medullary claudication). Another patient suffered progressive asymmetric paraparesis which first stabilized and later improved partially after surgical treatment of the aneurysm. The third suffered acute paraplegia related to irreversible ischemia of the anterior 2/3 of the medulla. The great variety of clinical manifestations of spinal cord ischemia related to aneurysms of the descending aorta can be explained by the topography of the aneurysm, pecularities of medullary vascularization and, especially, by the diversity of etiopathogenetic mechanisms that give rise to ischemia. We conclude that in the face of symptoms suggesting dorsal ischemic myelopathy, the possibility that an aneurysm of the abdominal aorta may be the cause must be considered, whether or not pain has been experienced prior to signs of medullary involvement.

Aged↗
PubMed1995

Molecular cloning of ion transporters: potential clinical implications.

The ion transporters are a group of integral membrane proteins which, like enzymes, can be regulated at multiple levels. Understanding of function and regulation of these proteins has been greatly facilitated by the knowledge of their molecular structures. In this article, we discuss the various approaches used in the cloning of these proteins. We then focus on genetic disorders known to be caused by abnormal structure of the transporter protein including cystic fibrosis, generalized myotonia and myotonia congenita, hyperkalemic periodic paralysis, hereditary ovalocytosis, hereditary spherocytosis and glucose malabsorption. Renal disorders thought, but not proved, to be due to abnormal transporter structure/function are briefly mentioned.

Cell Membrane↗
PubMed1995

[A decrease in the basal levels of serum pepsinogen I after H. pylori eradication].

Hyperpepsinogenaemia has long been considered an important factor in the pathophysiology of duodenal ulcer. Moreover, H. pylori infection has been reported in virtually all duodenal ulcers. OBJECTIVE. To demonstrate the influence of H. pylori eradication on basal pepsinogen I levels in patients with duodenal ulcer. METHODS. 86 patients with endoscopically proven duodenal ulcer were prospectively studied. Different therapeutic regimens were used: Amoxycillin/clavulanate plus omeprazole or ranitidine, triple therapy, omeprazole and ranitidine. At diagnostic endoscopy and after therapy, three biopsy samples were taken from different levels and analyzed by microbiological and histological methods; also, basal pepsinogen I levels were measured. RESULTS. H pylori eradication was associated with a significant histological improvement (p < 0.001), both in gastric antrum and corpus. In patients where H. pylori was eradicated pepsinogen I levels decreased from 107.6 +/- 31 ng/ml to 79.7 +/- 32 ng/ml after therapy (p < 0.001); however, when eradication was not achieved differences were not significant. CONCLUSION. H pylori eradication in patients with duodenal ulcer was associated with a significant decrease in basal pepsinogen I levels. The verification of such a decrease could represent a useful non-invasive method to monitor the efficiency of therapy, both in H. pylori eradication and in the resolution of the associated gastritis. This procedure is also associated with early results and a low cost.

Adult↗
PubMed1995

[Prevalence of Helicobacter pylori infection in gastrectomy and vagotomy].

OBJECTIVE: To report the prevalence of Helicobacter pylori infection in patients undergoing gastrectomy or vagotomy plus pyloroplasty because of peptic ulcer disease. METHODS: Eighty-five patients were studied (mean age = 61 years; 85% males) who had undergone gastric surgery: Billroth I gastrectomy (n = 25), Billroth II (n = 51) and vagotomy plus pyloroplasty (n = 9). During endoscopy biopsy specimens were obtained from fundus and both sides of anastomosis for histological (hematoxylin-eosin) and microbiological (Gram stain and culture) investigations. RESULTS: The overall percentage of Helicobacter pylori infection was 43.6% (Billroth I = 40%; Billroth II = 37%; vagotomy = 89%) and no differences were observed between both types of surgical reconstruction. However, differences were indeed observed (p < 0.01) when comparing percentages of infection between patients undergoing gastrectomy and vagotomy. Among infected gastrectomized patients H. pylori was detected in fundus in 93% of cases, whereas the recovery rate from anastomotic mouth biopsies was only 72% (p < 0.05). CONCLUSIONS: The prevalence of H. pylori infection in gastrectomized patients (Billroth I and II) was low regarding the cause of surgery (peptic ulcer disease), and no differences were observed between both types of surgical reconstruction. The prevalence of infection after vagotomy and pyloroplasty was significantly higher. Among infected gastrectomized patients, H. pylori was detected more frequently in gastric fundus compared with biopsy specimens obtained from the anastomotic mouth.

Adult↗
PubMed1995

Differential spatiotemporal expression of E- and P-cadherin during mouse tooth development.

Changes in E- and P-cadherin (E- and P-CD) expression during embryonic mouse first molar development were analyzed by immunohistochemistry. During the induction and morphogenesis stages (bud, cap and early bell stages), E-CD was expressed in the cells of the invaginating epithelial tooth bud and in the cells of the outer enamel epithelium, stellate reticulum and stratum intermedium, suggesting a role for this molecule in the maintenance of enamel organ architecture. On the other hand, P-CD was strongly expressed in the inner enamel epithelium suggesting its participation in the processes of mesenchymal induction. during the cytodifferentiation stage (late bell stage), E-CD was expressed in polarizing preameloblasts, but cadherin expression was restricted to the basal and apical poles of differentiated secretory ameloblasts, where the zonula adherens type of cell-cell junctions is located. The present study demonstrates for the first time the spatiotemporal expression of cadherins during tooth development and suggests differential and specific roles for E-CD and P-CD during the morphogenesis and cytodifferentiation processes of this organ.

Animals↗
PubMed1994

Influence of the ovary on parameters of LH secretion during the recovery from buserelin-induced desensitization.

This study examined the effect of the ovary on LH pulsatility and on the secretory performance of gonadotrophs during the phase of recovery after treatment with buserelin, a GnRH analogue. We included 12 patients, who received buserelin (1.2 mg/day, intranasally for 3 months) as a reductive therapy for uterine leiomyomatosis prior to hysterectomy. Six patients were oophorectomized and the other 6 patients had their ovaries preserved. LH was measured in samples taken basally up to 36 days after suppression of buserelin. LH pulsatility was studied on day 9 along a 24-h cycle, and the response of the hormone to a double-stimulus GnRH test on days 0, 9, 20, and 34. The concentration of LH reached normal premenopausal levels after an average of 2 weeks in women with ovaries but increased until 4-5 weeks in oophorectomized patients. The pulsatility of LH on day 9 was similar for both groups, but parameters related to LH amplitude or to baseline secretory activity of gonadotrophs were higher in the oophorectomized women. The response of LH to the GnRH tests was also significantly higher in the oophorectomized group from day 9. The conclusions are as follows. (1) At the early stage of recovery from desensitization, as represented by day 9, LH pulsatility was not substantially influenced by the presence or absence of the ovary. (2) There was an increase in parameters related to the amplitude of the LH bursts in the oophorectomized women. Although a higher amplitude of the endogenous GnRH pulses cannot be discarded, most probably that difference is due to a higher sensitivity at a pituitary level, as reflected by the GnRH stimulation tests.

Administration, Intranasal↗
PubMed1994

[Changes in the lipid profile in chronic hepatopathies].

BACKGROUND: The pattern of lipoproteins and apolipoproteins has been studied in a group of patients with chronic liver disease. The differences in this pattern were analysed in relation with the stage of liver disease and the presence of cholestasis. METHODS: Twenty one patients with hepatic cirrhosis and 12 with primary biliary cirrhosis were studied. Two subgroups were established according to the disease severity and to the Scheuer classification, respectively. Plasma lipoproteins were separated by ultracentrifugation, and the lipid and apolipoprotein composition were determined. Lipoprotein X was identified by means of agarose gel electrophoresis. RESULTS: In the subgroups with less severe liver disease, only minimal changes were found, such as the decreases in esterified cholesterol and Apo E contents in VLDL in the cirrhotic patients, and the increase of HDL-cholesterol in the patients with primary biliary cirrhosis in the first stages. In patients with severe hepatic cirrhosis, total esterified cholesterol, triglycerides, VLDL and HDL were diminished. Apo E in VLDL was undetectable whereas the different Apo C isoforms were in the normal proportion. Patients with severe biliary cirrhosis showed high levels of total cholesterol and triglycerides, elevated LDL-cholesterol, and decreased HDL-cholesterol and total esterified cholesterol. Apo C-IIO in VLDL was proportionally increased as related to both Apo E and Apo C-III. Lipoprotein X was detected in all these patients and in half of the patients with severe hepatic cirrhosis. CONCLUSIONS: Severe chronic liver disease is associated with a decrease of the concentration of hepatic lipoproteins and the absence of Apo E in VLDL, probably as a result of a defect in their synthesis. The lipid profile found in patients with biliary cirrhosis delineates the pattern of chronic cholestasis, which is characterized by the presence of lipoprotein X, a significant increase of free-cholesterol and a decrease of HDL-cholesterol; VLDL, which are increased, are rich in Apo C-II. Data show the distinct apolipoprotein composition of VLDL in the different hepatic diseases.

Adult↗
PubMed1994

Compliance to hormone replacement therapy in menopausal women controlled in a third level academic centre.

Compliance to distinct combinations of hormone replacement therapy was assessed in 331 postmenopausal women treated for 1 to 5 years in the Menopause Unit of a third level referral Academic Hospital. Forty nine women (15%) had interrupted therapy, mainly during the first year, while 29 (9%) never had their prescriptions filled. Forty five women (14%) followed the treatment intermittently or only sporadically completed the treatment as prescribed. Four main factors were analyzed for their eventual influence on compliance: the inclusion of progestins in the prescription, the source of referral, the severity of menopause-induced symptomatology, and the route of estrogen administration. The source of referral divided women into three groups: patients referred from a doctor, those addressed from the gynecology ward of the hospital, and women who directly asked to be taken as patients in the unit. The intensity of clinical manifestations was assessed through the Kupperman index. Only two variables, the addition of progestins (P < 0.02), and the oral route of estrogen administration (P < 0.01) determined lower levels of compliance. The other two factors did not induce significant changes in the attitude of the patients towards hormone therapy.

Administration, Cutaneous↗
PubMed1994

E-cadherin expression in basal cell carcinoma.

E-cadherin (E-CD) is a calcium-dependent cell-cell adhesion molecule which is expressed in almost all epithelial tissues. E-CD expression is involved in epidermal morphogenesis and is reduced during tumour progression of mouse epidermal carcinogenesis. It has been suggested that E-CD could play a role as an invasion-suppressor molecule. In the present work we have studied the E-CD expression in 31 patients with basal cell carcinoma (BCC) using an immunohistochemical technique with a monoclonal antibody (HECD-1) specific for human E-CD. E-CD expression was preserved in all specimens of superficial and nodular BCC, and was reduced in 10 of 15 infiltrative BCCs. A heterogeneous distribution of cells with different immunostaining intensity was more frequently observed in specimens of infiltrative BCC. These results suggest that E-CD might be related to the growth pattern and the local aggressive behaviour of BCC, and support the idea that E-CD might play a role as an invasion-suppressor molecule in vivo.

Adult↗
PubMed1994

Angiotensin II stimulation of Na-H antiporter activity is cAMP independent in OKP cells.

Angiotensin II has been reported to stimulate the proximal tubule Na-H antiporter by inhibition of adenylyl cyclase, and possibly by an adenosine 3',5'-cyclic monophosphate (cAMP)-independent mechanism. We examined the effect of angiotensin II on Na-H antiporter activity (JNa-H) in opossum kidney (OKP) cells, a proximal tubule-like cell line, whose Na-H antiporter resembles that of the proximal tubule apical membrane. We found that angiotensin II regulates JNa-H in a concentration-dependent manner similar to the proximal tubule, with angiotensin II concentrations < 10(-8) M stimulating and > 10(-8) M inhibiting JNa-H. The stimulatory effect of angiotensin II was blocked by 10(-8) M losartan and was pertussis toxin sensitive, suggesting mediation through an angiotensin II (AT1) receptor coupled to a pertussis toxin-sensitive G protein. Acute treatment with 10(-4) M 8-bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP) inhibited JNa-H by 30% and blocked angiotensin II-induced stimulation. However, angiotensin II (10(-12)-10(-6) M) did not inhibit basal, dopamine-stimulated, or forskolin-stimulated cAMP production measured in the presence of 3-isobutyl-1-methylxanthine (IBMX). In addition, angiotensin II had no effect on cAMP levels measured in the absence of IBMX. We conclude that angiotensin II at physiological concentrations stimulates JNa-H in OKP cells via a cAMP-independent mechanism mediated by an AT1 receptor and a pertussis toxin-sensitive G protein.

Adenylate Cyclase Toxin↗
PubMed1994

[An intrahepatic hematoma secondary to peliosis hepatis in a female patient treated with oral contraceptives].

The case of a patient is reported, who developed peliosis hepatis during contraceptive steroid therapy. This was clinically manifested as a spontaneous hepatic hematoma. No underlying liver tumor could be detected by both invasive and non-invasive investigations. Oral contraceptives should be listed among the potential albeit exceptional cases of liver hematoma, and this clinical presentation of peliosis hepatis added to the possible manifestations of that obscure condition.

Adult↗