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A Barton

Publications and source records attributed to A Barton.

At least 37 records · Page 2Linked to original sources

[Intussusception in adults].

The authors report eight cases of intussusception of small and large intestine in adults during five years. 3 of the intussusception caused by simple tumors in five cases by malignant. In three cases were chronic presented long term signs and symptoms. Ileo-ileal invagination was diagnostised at 3 patients, ileo-caecal in one case and ileocolic intussusception also in one case. In 2 cases developed caeco-colic, in one case colo-colic invagination. Resection was strongly indicated in seven cases and wedge resection was done at the last patient. One patient has died of cerebral multiple embilization. They review the etiology and pathology, the signs and symptoms as well as the difficulties during diagnosis and treatment of the intussusceptions according to their own experience and literary datas. The authors draw the attention to the importance of the modern iconographic, tools, particularly the ultrasonography in the diagnosis of intussusception.

Adolescent↗

Increased prevalence of sicca complex and fibromyalgia in patients with irritable bowel syndrome.

OBJECTIVE: As many as 70% of patients with fibromyalgia complain of the symptoms of irritable bowel syndrome (IBS), but there is a clinical impression that IBS patients do not suffer from fibromyalgia as frequently. The sicca complex (dry eyes and mouth) is also commonly observed in fibromyalgia, but its prevalence in IBS has not been evaluated. Our objective was to assess the frequency of fibromyalgia and sicca complex in secondary care patients with IBS. METHODS: Forty-six secondary care patients with IBS and 46 healthy controls were assessed by a rheumatologist for the presence of fibromyalgia and objective evidence of sicca complex (Schirmer and Rose-Bengal tests). Psychological status was also assessed (HAD questionnaire). RESULTS: Thirteen (28%) IBS patients suffered from fibromyalgia, compared with five (11%) controls, a difference of 17% (95% confidence intervals [CI], 2-33%). Fifteen (33%) IBS patients versus three (6%) controls had sicca complex, a difference of 27% (95% CI, 11-45%). CONCLUSIONS: These results suggest that the prevalence of fibromyalgia in IBS is approximately half that of IBS in fibromyalgia. Furthermore, sicca complex seems to be another complaint that should be added to the list of extracolonic manifestations of IBS. Study of the overlap between functional disorders presenting to different specialties may give new insights into the pathophysiology of these puzzling conditions.

Adult↗

Controlled comparative evaluation of BacT/Alert FAN and ESP 80A aerobic media as means for detecting bacteremia and fungemia.

During a one-year period, a total of 6,305 blood cultures were processed in a tertiary-care teaching hospital; 6 to 12 ml of blood was inoculated into both a BacT/Alert Fan aerobic bottle and an ESP 80A aerobic bottle. The FAN aerobic bottle contains an antimicrobial-absorbing material; the 80A aerobic bottle does not. Bottles were processed on their respective continuous-monitoring blood culture instruments for up to five days of incubation. Four hundred thirty-three cultures (6.9%) representing 301 septic episodes in 235 different patients yielded 490 bacteria or yeasts thought to be clinically significant. Two hundred seventy-five of the 433 presumed clinically significant positive cultures (63.5%) representing 195 septic episodes and yielding 301 isolates were positive in both FAN and 80A bottles. One hundred nine significant positive cultures (25.2%) (i.e., cultures positive with an organism judged to be of probable clinical significance) from 70 septic episodes yielded 126 isolates only in FAN bottles. Conversely, the 80A bottle was exclusively positive in 49 instances (11.3%), representing 36 septic episodes and yielding 63 isolates. The higher rates of significant positive blood cultures, numbers of septic episodes documented, and numbers of isolates recovered in FAN bottles versus 80A bottles were all statistically significant (P < 0.05). Enhanced rates of detection of presumed clinically significant isolates in FAN bottles were largely accounted for by Staphylococcus aureus, members of the Enterobacteriaceae, and non-Pseudomonas aeruginosa miscellaneous gram-negative bacilli from patients receiving antimicrobial therapy at the time blood cultures were obtained. Enhanced recovery of one organism group, the beta-hemolytic streptococci, occurred in 80A. With one exception, detection times were essentially equivalent in the two systems. The single exception pertained to streptococci and enterococci, which were recovered significantly faster in 80A bottles. Three hundred thirty-eight of the 6,305 blood cultures evaluated in this study (5.4%) were judged likely to be contaminated. The percentages of probable contaminated cultures were as follows: 26.6% FAN and 80A; 42.3% FAN only; 31.1% 80A only (P < 0.05). Finally, the instrument false-positive rates for the two systems were 0.7% with FAN and 3.0% with 80A (P < 0.05). We conclude that while contamination rates were slightly higher with FAN than with 80A, use of FAN aerobic bottles in conjunction with the BacT/Alert system will yield significantly higher numbers of clinically significant blood culture isolates than 80A bottles and the ESP system. Furthermore, this enhanced detection is most conspicuous in patients receiving antimicrobial therapy at the time blood cultures are performed, probably due to the presence of an antimicrobial-absorbing material in FAN aerobic bottles.

Bacteremia↗

Calciphylaxis: one hospital's experience.

The lives of the ESRD population have been enhanced and prolonged by improved conservative management, efficient dialysis and successful transplantation. However, practitioners are noting some significant morbidity in these long-term surviving nephrology patients. Clinical signs of renal osteodystrophy can be very subtle and insidious. Bone pain, muscle weakness, and pruritus can be vague symptoms. Calciphylaxis, which is classified as a skin disorder is an extremely rare, painful, and progressive complication. Typically, the patient presents with vascular calcifications, cutaneous ulcerations and tissue necrosis. The treatment regimen for bone disease in the ESRD population will be reviewed. The symptoms of calciphylaxis, diagnostic tests and prognosis will be discussed. Four case studies describe our recent experience. Emphasis will be on the intense multidisciplinary care required for this devastating and often fatal syndrome.

Adult↗

IgE secretion is attenuated by an inhibitor of proteolytic processing of CD23 (Fc epsilonRII).

CD23, the low-affinity IgE receptor, is up-regulated on interleukin (IL)-4-stimulated B cells and monocytes, with a concomitant increase in the release of soluble fragments of CD23 (sCD23) into the medium by proteolytic processing of the surface-bound intact CD23. The effect of inhibition of the processing of CD23 on IgE production in human and mouse cells and in a mouse model in vivo was evaluated. CD23 processing to sCD23 from RPMI 8866 (a human Epstein-Barr virus-transformed B cell line) cell membranes was inhibited by a broad-spectrum matrix-metalloprotease inhibitor, batimastat, with an IC50 of 0.15 microM. Batimastat also inhibited CD23 processing in whole RPMI 8866 cells as well as in IL-4-stimulated purified human monocytes with similar IC50. Batimastat inhibited IgE production from IL-4/anti-CD40-stimulated human tonsil B cells as well as mouse splenic B cells in a manner consistent with inhibition of CD23 processing. Release of soluble fragments of CD23 in the cell supernatants of tonsil B cells was inhibited over the concentration range of 1-10 microM batimastat and intact cell surface CD23 was increased on mouse splenic B cells in the presence of these concentrations of batimastat. IgE production of IL-4-stimulated human peripheral blood mononuclear cells was also blocked by 1-10 microM batimastat, again with comparable inhibition of sCD23 release over the same concentration range. Finally, in a mouse model of IgE production, batimastat inhibited IgE production in response to ovalbumin challenge as determined by serum IgE levels. Taken together, the data support a role of CD23 in IgE production and point to CD23 processing to sCD23 as a therapeutically relevant control point in the regulation of IgE synthesis.

Animals↗

Mycobacterium marinum infection causing septic arthritis and osteomyelitis.

A 48-yr-old female on immunosuppressive therapy for fibrosing alveolitis and polymyositis developed a septic arthritis of the left middle finger proximal interphalangeal joint, tenosynovitis of the left palm and osteomyelitis of the right hindfoot due to infection with Mycobacterium marinum. Such widespread and severe bone and joint involvement has not been described previously with this organism.

Anti-Bacterial Agents↗

Peroxynitrite augments fMLP-stimulated chemiluminescence by neutrophils in human whole blood.

The neutrophil respiratory burst was examined by the technique of luminol-dependent chemiluminescence (LDCL) triggered by submaximal concentrations of N-formyl-methionyl-leucyl-phenylalanine (fMLP) in diluted whole blood. We sought to identify the chemical species responsible for LDCL in whole blood, to examine the role of leukotriene B4 (LTB4) and other arachidonic acid metabolites as mediators of the fMLP signaling pathway, and to investigate the effect of peroxynitrite on this response. Both sodium azide and taurine significantly inhibited LDCL (93% inhibition with 100 microM azide, 52% inhibition with 10 mM taurine). More modest inhibition was seen with superoxide dismutase (SOD), catalase, the nitric oxide synthase inhibitor monomethyl-L-arginine (L-NMMA), and with inhibitors of the cyclooxygenase (indomethacin), lipoxygenase (AA-861; no effect), and cytochrome P-450 (SKF 525-A) pathways of arachidonic acid metabolism. The nitric oxide donor SIN-1 (1-100 microM) and peroxynitrite (10-300 microM) also augmented fMLP-induced LDCL. The augmentation seen with peroxynitrite and SIN-1 was attenuated by SOD. Despite the increase in LDCL, peroxynitrite caused a dose-related inhibition of fMLP-stimulated LTB4 release. In summary, our results indicate that (1) LDCL elicited by fMLP in diluted whole blood appears primarily mediated by hypochlorous acid derived from myeloperoxidase; (2) pretreatment with the nitric oxide donor SIN-1 or with peroxynitrite augments LDCL; and (3) LTB4 release does not contribute to fMLP-stimulated LDCL or in the modulation of LDCL by SIN-1 or peroxynitrite.

Antioxidants↗

Resection of olfactory groove meningiomas: technical note revisited.

BACKGROUND: Although large olfactory groove meningiomas present in the midline, tumor volume is often unequally distributed to one side. Most surgeons favor a bifrontal craniotomy with retraction or partial resection of the frontal lobes to resect these tumors. However, frontal lobe retraction is not without complications. METHODS: We present a technical note regarding the resection of these large olfactory groove meningiomas. We describe the advantages of a unilateral frontal craniotomy complemented with orbital osteotomy. RESULTS: The orbital osteotomy has considerably reduced the need for frontal lobe retraction and avoids partial resection of the frontal lobe to uncap the tumor. Utilizing this approach we have been able to remove the tumor from one side, followed by an incision to the falx cerebri in order to remove the tumor from the other side. With this approach, we have gained excellent visualization of the tumor in its entirety. Moreover, this approach permits the surgeon to intercept the arteries emerging from the skull base during the initial stages of the procedure. CONCLUSIONS: Unilateral frontal craniotomy and orbital osteotomy has obviated the need to retract or resect the frontal lobe when resecting large olfactory groove meningiomas, which extend to either side of the falx. Because surgery is performed from one side, olfaction may also be preserved on the contralateral side.

Aged↗

CD23-mediated homotypic cell adhesion: the role of proteolysis.

CD23 is a multifunctional molecule expressed by cells of lymphoid, myeloid and hematopoietic lineages. As a cell surface molecule CD23 acts both as a low-affinity receptor for IgE (Fc epsilon RII) and as a cell adhesion molecule. CD23 can undergo autoproteolysis to release soluble 37-25-kDa CD23 (s-CD23) molecules with a range of cytokine activities. Here we show a causal link between the two apparently disparate functions of autoproteolysis and cell adhesion. The Epstein-Barr virus-transformed B cell line RPMI-8866 formed macroscopic cell clusters solely via CD23. Cell adhesion was inhibited by mAb to CD23 and by IgE. Cell adhesion was also dependent on serum as cells grown in serum-free media failed to form clusters. In serum-free conditions cell adhesion could be induced by the addition of not only 10% FCS but also s-CD23. As s-CD23 is reported to possess proteolytic activity we screened a range of proteases to determine whether they also could induce cell adhesion in serum-free medium. It was found that chymotrypsin and elastase induced cell:cell adhesion in RPMI-8866 cells. The same panel of proteases were screened against a range of CD23-positive (Jijoye, AF-10, T2, U937, ICH-1) and CD23-negative (RPMI-8226, U266, MOLT-4, Ramos) cell lines. It was found that chymotrypsin and elastase induce cell adhesion only in cells expressing CD23. Peptide mapping studies showed that chymotrypsin and elastase cleaved immunoprecipitated CD23 near the same site by which 37-kDa s-CD23 is released (Ala 80). Serum demonstrated no proteolytic activity towards CD23. However, it was found that cells grown in serum-free medium released 25-kDa s-CD23 without the need for prior cleavage at the 37-kDa cleavage site. To confirm the role of proteolysis in CD23-mediated cell adhesion we screened a range of protease inhibitors for their ability to antagonize this process. It was found that tosyl-lysine chloromethyl ketone inhibited CD23-mediated cell adhesion. Lactoperoxidase treatment, which inhibits CD23 cleavage, also inhibited cell adhesion. Addition of chymotrypsin and elastase to lactoperoxidase-treated cells induced cell adhesion. From these data we propose that intact CD23 has no demonstrable role in cell adhesion; instead, the portion of CD23 remaining on the cell surface following cleavage appears to mediate cell adhesion.

Blood Physiological Phenomena↗