Biomedical subjects

A Oler

Publications and source records attributed to A Oler.

33 records · Page 2Linked to original sources

PubMed1996

Innervated liver plays an inhibitory role in regulation of food intake.

BACKGROUND: With the onset of eating, the associated rise of dopamine in the lateral hypothalamus (LHA-DA) is thought to regulate quantity of food consumed per meal. Early release of LHA-DA induced by eating is facilitated by oronasal stimulation; we propose that the subsequent LHA-DA response induced by nutrients in the portal vein is dampened by the innervated liver. This was tested by measuring LHA-DA in normal rats: during parenteral feeding to bypass oronasal stimulation, while eating during parenteral feeding, and while eating only. METHODS: Rats had either total liver denervation or sham operation, with placement of a jugular vein catheter and LHA-DA microdialysis cannula. After a 3-week recovery period total liver denervated rats were randomized to parenterally fed, food only, and parenteral plus food groups each with sham-operated controls in which LHA-DA was measured. RESULTS: No difference in LHA-DA release in food only groups occurred between total liver denervated or sham-operated rats. A significantly higher rise in LHA-DA was observed in total liver denervated versus sham-operated rats in parenterally fed (129% +/- 4% versus 116% +/- 2%; p < 0.05) and parenteral plus food (151% +/- 4% versus 134% +/- 4%; p < 0.05) groups. CONCLUSIONS: In total liver denervation versus sham operation, an increase in LHA-DA release occurs during parenteral feeding and eating during parenteral feeding, suggesting that innervated liver inhibits LHA-DA release.

Animals↗

PubMed1996

Mode of food intake reduction in Lewis rats with indomethacin-induced ulcerative ileitis.

The mechanism of anorexia in inflammatory bowel disease is poorly understood. To gain insight into possible pathophysiologic mechanisms, the feeding indices and food intake were studied in an animal model of Crohn's disease. The anorexia of indomethacin-induced ulcerative ileitis was compared with that of the well-known anorexia of total parenteral nutrition (TPN). Forty-five female Lewis rats were randomized to four groups: Control, Indomethacin, Indomethacin + TPN, and TPN. Feeding indices and food intake were continuously measured using the Automated Computerized Rat Eater Meter. Interleukin-1 alpha (IL-1 alpha), tumor necrosis factor-alpha (TNF-alpha), prostaglandin E2 (PGE2), and leukotriene B4 (LTB4) were assayed in plasma, mononuclear cell culture, or ileum to determine their role in mediating anorexia. In the TPN group, spontaneous food intake (SFI) decreased (52%; p < 0.05), primarily via reduction in meal number (MN, 54%; p < 0.05) and, to a lesser extent, meal size (MZ, 35%; p < 0.05). In comparison, in the Indomethacin group SFI decreased (74%; p < 0.05) primarily via reduction in MZ (67%, p < 0.05); MN also decreased but to a lesser extent (27%; p < 0.05). In the Indomethacin + TPN group, SFI decreased (55%; p > 0.05) primarily via reduction in MN (79%; p < 0.05), whereas MZ decreased slightly (19%; p < 0.05). Only in the Indomethacin group were IL-1 alpha and TNF-alpha detected in the mononuclear cell culture and plasma, respectively. In the Indomethacin group, an inverse correlation existed between MZ and TNF-alpha (p < 0.05). In the Indomethacin group, IL-1 alpha, PGE2, and LTB4 concentrations did not correlate with feeding indices. SFI reduction in this model was mediated primarily via a decrease in MZ. TNF-alpha is proposed to mediate this effect and TPN was shown to overcome the effect on MZ.

Animals↗

PubMed1995

Pathogenesis-based treatment of recurring subareolar breast abscesses.

BACKGROUND: When a subareolar breast abscess (SBA) is incised and drained, an extraordinarily high frequency of recurrence is noted. METHODS: To develop a pathogenesis-based treatment plan, 24 women with a total of 84 abscesses were monitored. RESULTS: In nine women SBA was under the left areola, under the right, in 7 and in eight the SBA occurred either simultaneously or sequentially under both areolae. In 11 of 24 patients a chronic lactiferous duct fistula also existed. In four of 24 patients four SBAs were treated with antibiotics; alone; all recurred. In 16 of 24 patients initial treatment was incision and drainage plus antibiotics; all recurred. When the abscess plus the plugged lactiferous duct was excised, there were no recurrences; however, in four patients a new abscess in a different duct occurred, which was treated by en bloc resection of all subareolar ampullae, without further recurrence. Patients with a fistulous tract had the fistula, its feeding abscess, and its plugged lactiferous duct excised, without recurrence. In first time SBA the organism was usually staphylococcus; in recurrences mixed flora was isolated. Pathologic findings ranged from squamous metaplasia with keratinization of lactiferous ducts to chronic abscess. CONCLUSIONS: The cause of SBA is plugging of lactiferous duct within the nipple by keratin. To prevent recurrence the abscessed ampulla with its plugged proximal duct needs excision.

Abscess↗

PubMed1994

The prognostic significance of neuroendocrine markers and carcinoembryonic antigen in patients with resected stage I and II non-small cell lung cancer.

Non-small cell lung cancer with neuroendocrine differentiation may represent a subset of patients with a more aggressive (like small cell lung cancer) or less aggressive (like carcinoid) biological behavior. To investigate their prognostic significance, immunohistochemical stains for 4 neuroendocrine markers (neuron-specific enolase, chromogranin A, Leu-7, and synaptophysin) and carcinoembryonic antigen (CEA) were studied in 260 patients with surgically resected stage I and II non-small cell lung cancer. The following percentages of cases were positive for each marker: neuron-specific enolase, 70.0%; chromogranin A, 14.2%; Leu-7, 7.7%; synaptophysin, 11.2%; and CEA, 68.5%. Sixty-one (23.5%) were positive for > or = 2 neuroendocrine markers. When compared to adenocarcinoma, squamous cell carcinoma displayed lower positivity for CEA and > or = 2 neuroendocrine markers. There was no significant difference in stage, site of relapse (distant versus local), disease-free, or overall survival for each marker individually or for those with > or = 2 neuroendocrine markers. Multivariate analysis showed that higher nodal stage (N1 versus N0), tumor stage (T2 versus T1), older age, and the presence of mucin predicted for poorer overall survival. Neuroendocrine markers and CEA were not of prognostic significance in this group of patients with resected stage I and II non-small cell lung cancer.

Adult↗

PubMed1991

Ca(2+)-independent form of protein kinase C may regulate Na+ transport across frog skin.

Activators of protein kinase C (PKC) stimulate Na+ transport (JNa) across frog skin. We have examined the effect of Ca2+ on PKC stimulation of JNa. Both the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) and the diacyl-glycerol sn-1,2-dioctanoylglycerol (DiC8) were used as PKC activators. Blocking Ca2+ entry into the cytosol (either from external or internal stores) reduced the subsequent natriferic effect of the PKC activators. This negative interaction did not simply reflect saturation of activation of the apical Na+ channels, since the stimulations produced by blocking Ca2+ entry and adding cyclic AMP were simply additive. The Ca2+ dependence of the natriferic effect could have reflected either a direct action of cytosolic Ca2+ on PKC or an indirect action on the final receptor site (the Na+ channel). To distinguish between these possibilities, the TPA- and phospholipid-dependent kinase activity of broken-cell preparations was assayed. The kinase activity was not stimulated by physiological levels of Ca2+, and in fact was inhibited at millimolar concentrations of Ca2+. We conclude that the effects of Ca2+ on the natriferic response to PKC activators are indirect. Reducing cytosolic uptake of Ca2+ may have stimulated Na+ transport by a chemical modification of the apical channels observed in other tight epithelia. The usual stimulation of Na+ transport produced by PKC activators in frog skin may reflect the operation of a nonconventional form of PKC. This enzyme is Ca2+ independent and seems related to the nPKC or PKC epsilon observed in other systems.

Amiloride↗

PubMed1990

Liver biochemical and histological changes with graded amounts of total parenteral nutrition.

We sought to determine whether an excess in energy intake as total parenteral nutrition would result in liver biochemical and histological changes in the presence of a functional gastrointestinal tract. Three groups of rats were given amounts of total parenteral nutrition that provided either 25% (total parenteral nutrition-25), 100% (total parenteral nutrition-100), or 200% (total parenteral nutrition-200) of a rat's energy requirements. Rat chow and water were available ad libitum. Food intake decreased in proportion to the amount of total parenteral nutrition infused; it ceased with total parenteral nutrition-200. Liver glycogen and triglyceride concentrations were higher with high energy intake (total parenteral nutrition-100 and total parenteral nutrition-200), while total liver nitrogen concentrations remained unchanged. No cholestasis, inflammation, or fibrosis was seen histologically. Fatty vacuoles were increased with total parenteral nutrition (more so with total parenteral nutrition-200) but a prompt return to normal liver features was observed after cessation of total parenteral nutrition and the resumption of normal food intake.

Animals↗

PubMed1989

Ability of a benign tumor to decrease spontaneous food intake and body weight in rats.

Malignant tumors induce anorexia and decrease spontaneous food intake and weight loss. Whether these effects are in part due to the tumor's physical size was investigated by inducing a benign cystic tumor mass with carrageenan in rats and then studying them for 21 days. Forty-two control rats were given subcutaneous injection of 3 ml of normal saline. Fifty-six study rats were given 3 ml of a 1.5% carrageenan solution subcutaneously, both in the right flank. Daily spontaneous food intake, body weight, and tumor weight were measured. Eight study and six control rats were randomly sacrificed on days 1, 3, 5, 7, 10, 14, and 21. Blood was obtained by cardiac puncture for albumin determination, and the tumor, carcass, liver, and spleen were removed and weighed. Tumor and tissue samples were histologically examined. All rats injected with carrageenan developed a benign cystic tumor mass. Early cystic wall consisted mainly of foamy macrophages with a light lymphoplasmacytic chronic inflammatory infiltrate and moderate vascularization. At day 21, cystic wall was more compact. The vasculature had collapsed and there were more pronounced fibroblastic response and collagen bundles. Average tumor weight by day 21 was 41 g. Average spontaneous food intake was depressed by about 15% from day 8 on in study rats as compared to controls. A significant decrease in carcass weight of 15.2% was observed in study as compared to control rats at day 21. Serum albumin was significantly decreased in study rats after day 5. Liver weight was significantly lower and spleen weight higher in study rats as compared to controls. These data suggest that some characteristics associated with cancer anorexia can be found in the absence of malignancy.

Animals↗

PubMed1989

The use of neuroendocrine immunoperoxidase markers to predict chemotherapy response in patients with non-small-cell lung cancer.

Small-cell lung cancer (SCLC), a chemotherapy-responsive disease, is characterized by neuroendocrine properties. In contrast, non-small-cell lung cancer (NSCLC) is at best moderately responsive to chemotherapy, and only 10% to 20% of cases demonstrate neuroendocrine properties. The present study is a retrospective analysis of the use of immunoperoxidase markers for neuron-specific enolase (NSE), Leu-7, and chromogranin A in NSCLC patients treated with chemotherapy. It was designed to determine if the presence of neuroendocrine markers predict for response to chemotherapy. The diagnostic slides and blocks were obtained on 52 NSCLC patients who were treated with chemotherapy (26 responders and 26 nonresponders). Immunoperoxidase studies were performed, and slides were scored without knowledge of the patient's response. Markers were positive in responders and nonresponders, respectively, as follows: NSE, 14 of 26 (54%) versus seven of 26 (27%), P = .04; Leu-7, 11 of 25 (44%) versus five of 26 (19%), P = .08; and chromogranin A, three of 26 (12%) versus 0 of 26 (0%), P = .71. Two markers were positive in 10 of 26 responders (38%) and 0 of 26 nonresponders (0%), P less than .01. Responders with two or more positive markers showed superior survival (median, 79 weeks) compared with responders with fewer than two positive markers (median, 51 weeks) and nonresponders (median, 27 weeks). These data suggest that the presence of neuroendocrine markers in NSCLC is associated with an increased likelihood of response to chemotherapy and may add to the standard parameters (performance status, weight loss) used to select patients for chemotherapy.

Adult↗

PubMed1976