Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0155339 (Brown)
 12,436 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chronic toxicity and carcinogenicity of levobunolol, a nonselective beta-adrenoceptor antagonist, was evaluated in Swiss mice and Wistar rats. The drug was administered in the diet to mice at 0, 12, 50, and 200 mg/kg/day for 80 weeks and to rats at 0, 0.5, 2, 5, 30, and 180 mg/kg/day for 2 years. In mice, uterine leiomyomas were present in 4 of 50 females at 200 mg/kg but not in any other group. The incidences of other tumor types, as well as pathologic findings, were comparable among groups. In rats, significant body weight gain suppression occurred at 5, 30, and 180 mg/kg. Brown discoloration of perianal fur and steel-gray discoloration of hairless skin were evident in high-dose rats. A generalized steel-gray discoloration of internal organs and tissues occurred in the 30 and 180 mg/kg groups. No other differences between treated and control groups were evident. The clinical relevance of the increased incidence of uterine leiomyoma in mice is questionable because it occurred only in one species at more than 200 times the projected therapeutic dose.
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PMID:Chronic toxicity and carcinogenicity studies with the beta-adrenoceptor antagonist levobunolol. 135 Jul 67

The signal transduction mechanisms involved in the regulation of phagocytosis are largely unknown. We have recently shown that in neutrophils, when IgG-mediated phagocytosis is stimulated by formyl-methionyl-leucyl-phenyl-alanine (fMLP), the enhanced ingestion is dependent on the increase in [Ca2+]i which results from ligation of Fc receptors by the IgG-coated target (Rosales, C., and Brown, E. (1991) J. Immunol. 146, 3937-3944). Now, we have studied the mechanism by which this rise in [Ca2+]i occurs. Aggregated IgG, the monoclonal antibody 3G8 (which recognizes Fc receptor type III), and insoluble immune complexes caused an increase in [Ca2+]i. The rise in [Ca2+]i induced by Fc receptor ligation was resistant to pertussis toxin. In contrast, fMLP induced a rise in [Ca2+]i which was inhibited by pertussis toxin. fMLP-induced [Ca2+]i was accompanied by an accumulation of inositol 1,4,5-trisphosphate (IP3) which peaked by 15 s, and which was also abolished by pertussis toxin. IP3 accumulation after aggregated IgG, 3G8, or insoluble immune complexes was much less than after fMLP. Unlike [Ca2+]i rise induced by Fc receptor ligation, this small increase in IP3 was inhibited by pertussis toxin. These data demonstrated that the [Ca2+]i increase induced by Fc receptor ligation is not mediated by IP3. Immediate pretreatment of human polymorphonuclear neutrophils with optimal doses of fMLP also reduced subsequent increase in [Ca2+]i rise from thapsigargin, a sesquiterpene lactone tumor promoter that releases intracellular Ca2+ from IP3-sensitive stores without IP3 turnover. Similarly, to its effects on thapsigargin, fMLP inhibited the [Ca2+]i rise upon subsequent immune complex binding. Pretreatment of cells with immune complexes also prevented subsequent [Ca2+]i rise from thapsigargin and fMLP. These data demonstrate that IgG Fc receptor ligation and fMLP activation of human polymorphonuclear neutrophils use distinct signal transduction mechanisms to release Ca2+ from the same thapsigargin-sensitive intracellular pool. In contrast to fMLP, signal transduction for increased [Ca2+]i after Fc receptor stimulation does not involve a pertussis toxin-sensitive G protein, and is independent of IP3.
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PMID:Signal transduction by neutrophil immunoglobulin G Fc receptors. Dissociation of intracytoplasmic calcium concentration rise from inositol 1,4,5-trisphosphate. 153 82

The authors have developed new devices for stereotactic radiosurgery using a conventional linear accelerator (LINAC). The system of devices consists of a rotatory chair with a base ring holder, a Brown Robert Well's stereotactic apparatus (BRW's apparatus) with a double set of base rings and a number of precise collimators which eliminate penumbra to the greatest extent. A study rotatory chair was manufactured, whose vertical axis of rotation is always set and stable. A strongly built, adjustable holder for the BRW's base ring is attached to the chair. The principle and flow of procedures step by step is as follows; 1). The rotatory chair is carried in under the linear accelerator and the vertical rotatory axis of the chair is precisely adjusted to align with the vertical center of the photon beam from the LINAC. 2) A base ring and a locator of BRW's apparatus are mounted on a patient's head and three coordinates of a target are determined by CT scans. 3) The target indicator of the dummy set of BRW's apparatus is positioned according to X, Y, Z coordinates of the target. The tip of a rod indicator fixed on an instrument bloc on the arc device is precisely adjusted to touch at the tip of the target indicator. 4) The base ring and arc device with rod indicator are transferred together from the BRW's dummy set to the rotatory chair and fixed to the base ring holder. The tip of the rod indicator is precisely adjusted to be positioned at the isocenter of the LINAC. 5) The base ring and arc device are removed and replaced by another base ring mounted on the head of a patient, who is made to sit on the rotatory chair. The target in the brain is now located at the isocenter of the LINAC. Stereotactic radiation is started with rotation of the chair and circular movement of the gantry of the LINAC. The chair is rotated at a speed of 100 degrees per second, and the gantry of the LINAC is moved slowly on a circular trajectory from +115 degrees to -115 degrees. Fourteen cases, including AVM, cavernous angioma, acoustic tumor and glioma have been treated so far. Three cases of large AVM were treated by a combination of artificial embolization and stereotactic radiosurgery.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[A new principle and device for radiosurgery using a linear accelerator; its principle, devices and clinical trials]. 159 34

In the operative resection of brain tumors, defining and locating edges of deep-seated tumors or those with indistinct color and consistency can be difficult. This report presents a simple yet precise, alternative method, using the basic Brown-Roberts-Wells or Cosman-Roberts-Wells stereotactic frame, for placement of visual markers to aid in tumor resections. The method can also be extended to the Leksell system. Using routine computed tomographic scanning or magnetic resonance imaging after stereotactic frame application, multiple points along tumor edges were used as target points. In the operating room, standard techniques were used for the skin incision, removal of the bone flap, and opening the dura. At each target point, after opening the dura and using stereotactic coordinates and equipment, a microbiopsy forceps was used to place "micropatties" (each with a string tail) or small catheters with pledgets or catheter tips located at tumor edges. After removing the arc, the tumor resection was accomplished in a conventional nonstereotactic manner by simply following string tails or catheters to the tumor. Gross tumor edges were determined from positions of actual patties or catheter tips. These simple but accurate techniques offer the possibility of tumor resections under stereotactic guidance with equipment readily available to most neurosurgeons. The fidelity of marker placement is also maintained in relation to tumor edges despite shifts in the tumor and/or brain as cystic areas are drained or large amounts of the tumor are resected.
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PMID:Brain tumor resection aided with markers placed using stereotaxis guided by magnetic resonance imaging and computed tomography. 164 77

Six children ranging in age from 2 to 10 years who harbored deep benign astrocytomas were operated upon using a computer- and robot-assisted system. A radical excision was achieved in all cases with no significant morbidity nor any mortality. The system consists of an interactive, three-dimensional display of computed tomographic image contours and digitized cerebral angiograms taken using the Brown-Roberts-Wells stereotactic frame. The surgical retractor is held and manipulated using a PUMA 200 robot. The position and orientation of the surgical retractor is displayed on the three-dimensional display. Preoperative planning and simulation are important features of this system. Movement of the brain after removal of the tumor and cerebrospinal fluid is substantial, so the tumor removal is based on visually defined margins. Enhanced computer graphics and robotic devices are important adjuncts to neurosurgical procedures and will find increasing use in the future.
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PMID:Computer- and robot-assisted resection of thalamic astrocytomas in children. 187 Jun 84

The paper reports the case of a maxillary brown tumor as early sign of primary hyperparathyroidism. Brown tumors are very unusual growths in daily ENT practice and an odd start of primary hyperparathyroidism. The AA. emphasize the importance of a correct differential diagnosis, especially with those tumors showing multinucleated giant cells (osteoclast type)--such as true giant cells tumor and central giant granuloma--prior to its management. They also comment on the interesting contribution to diagnosis by imagery brought by CT scan, magnetic resonance (MR), ultrasonography (echography) and digital subtraction gammagraphy to attain the topographic site of the parathyroid tumor.
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PMID:[Brown tumor of the maxilla as initial manifestation of primary hyperparathyroidism]. 189 10

Thirty-one cervical carcinomas have been studied immunohistochemically to determine tumor growth fraction by using the monoclonal antibody Ki-67, which reacts with a nuclear antigen expressed only by proliferating cells. The growth fraction of individual tumor is estimated as the percentage of stained nuclei in a population of 1000 tumor cells. There is a good correlation of the growth fraction measured by Ki-67 with mitotic index and high histological grade of cervical carcinoma. This study, together with that of D. C. Brown, D. Cole, K. C. Gatter, and D. Y. Mason [Brit. J. Cancer 57(2), 178-181 (1988)], shows the usefulness of Ki-67 in the evaluation of growth fraction in cervical carcinoma.
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PMID:Tumor growth fraction in cervical carcinoma. 198 15

In recent years, a great advance has been brought in an early detection of colorectal cancer, especially early colorectal cancer. But some controversies are present as follows: 1. Mass screening for colorectal cancer. Immunologic tests for fecal occult blood increased the sensitivity and specificity for detecting colorectal neoplasia without a question. However, this screening method has not proven to get the effectiveness in decreasing mortality of colorectal cancer, although a case control study is under way in our department. 2. Adenoma-carcinoma sequence or de nov carcinoma. These two theories on histogenesis of colorectal cancer are on "hot" discussion to be better understood. 3. Strip biopsy for colorectal lesions. This method is now begun to be introduced to apply for small type-II lesions of colon. 4. Others (barium enema or endoscopy, a new method of colonic preparation which replaces Brown's method, tumor marker in colorectal cancer etc.). Today's status and future prospects were made on these matters.
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PMID:[Controversies in early detection of colorectal cancer]. 201 94

The role of life events in breast cancer was conceptualized within two models differing by vulnerability factors, 'social support' and 'early loss of mother'. The eight years prior to manifestation of the lump were covered by semi-structured interviews. Event ratings were performed according to Brown and Harris' Life Events and Difficulties Scale, an interviewer-based rating method. Data were collected within a so-called limited prospective design. This setting was subject to critical evaluation to control possible artifacts. Interviews were tape-recorded and rated before learning the final diagnosis. In the tumor groups, 97 women with a suspicious breast lump were interviewed immediately after hospital admission. In 33 cases, the diagnosis turned out to be malign, 59 had a benign result. Data analysis revealed that life events in the severest categories were reported most often in the cancer group. Path analyses showed that effects do not disappear when control variables are taken into account.
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PMID:Life events prior to manifestation of breast cancer: a limited prospective study covering eight years before diagnosis. 204 66

When excision of the tumor infiltration of the duodenum is followed by formation of a small defect, the authors apply a personal modification of two-story suture. Then the duodenal suture is fully covered with the serosa of the small-intestinal loop. Thus the suture is hermetically sealed and remains in a relative rest. When a large defect remains after excision of the tumor infiltration of the duodenum, a short jejunal loop is taken and a longitudinal section is made on it of equal length with that of the duodenal defect. Laterolateral anastomosis is made between the duodenal defect and the jejunum. Brown's anastomosis is made somewhat distally from the duodenojejunostomy. In this way the duodenum is not narrowed, the tissues are sutured without any tension and postoperative duodenal stasis is minimal. The first variant of the method was applied in 3 patients and the second in 3 patients with very good postoperative result.
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PMID:[The use of a new method for the restoration of duodenal passage following the partial extirpation of its wall in treating locally advanced tumors of the right half of the colon]. 209 37


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