In vivo electrochemical demonstration of potassium-evoked monoamine release from rat cerebellum

In vivo electrochemical methods were employed to study the potassium (K⁺-evoked release of monoamines from the cerebellum of the chloral hydrate anesthetized rat. K⁺-evoked releases were elicited using micropipette-Nafion-coated graphite epoxy electrode arrays in the granule/Purkenje cell layer, molecular layer, and white matter. These recorded releases were generally found to be reversible, moderately dose-dependent, and reproducible. However, the temporal dynamics of the releases were different for the cell layer versus molecular layer records. Releases were infrequently observed in cerebellar white matter, an area which is relatively devoid of monoamine containing terminals. The signals recorded from the cell and molecular layers were significantly attenuated by pretreatment with nomifensine, a potent catecholamine reuptake blocker, significantly prolonged the K⁺-evoked signals observed in both the granule/Purkenje cell and molecular layers. These data, taken together with earlier reports on the electrophysiological responses to activation of cerebellar noradrenergic inputs, support the conjecture that in vivo electrochemical recording methods have the sensitivity and spatial resolution for studies of functional monoamine release from brain regions that have a diffuse or laminated monoamine innervation.     

Pseudomonas aeruginosa als Erreger opportunistischer Infektionen

Zusammenfassung Pseudomonas aeruginosa ist ein ubiquitär vorkommender Mikroorganismus, der aber als Bestandteil der endogenen mikrobiellen Flora gesunder Individuen nur selten isoliert wird. Die Hospitalisierung, die Krankenhausverweildauer erhöhen die Kolonisationsrate insbesondere bei immunsupprimierten Patienten signifikant. Eine Antibiotikatherapie oder -prophylaxe wie auch invasive diagnostische Maßnahmen begünstigen ebenfalls eine Besiedlung und Infektion der Patienten mitP. aeruginosa. Immundefekte der Patienten sowie eine negative Interaktion vonP. aeruginosa mit dem Immunsystem wirken infektbahnend. Somit begünstigen eine Vielzahl exogener wie endogener Faktoren und deren Wechselwirkungen das Auftreten vonP. aeruginosa-Infektionen.

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Opportunistic infections caused by pseudomonas aeruginosa

Summary Pseudomonas aeruginosa, in spite of being an ubiquitous microorganism, rarely colonizes healthy individuals. Hospitalization, as well as the length of time spent in hospital, significantly increase the rate of colonization, especially in immunocompromized patients. Antibacterial chemotherapy or prophylaxis together with invasive diagnostic procedures favour colonization and infection withP. aeruginosa. Immune deficiencies and adverse interactions ofP. aeruginosa with the immune system facilitate infection. Thus, a number of exogenous as well as endogenous factors and their interactions favour infection of patients withP. aeruginosa.

     

Radiotherapy in the management of pancreatic islet cell tumors

Malignant islet cell tumors are commonly treated with surgical resection. Chemotherapy is reserved for residual, unresectable, or metastatic disease. The role for radiotherapy has not been clearly defined. This article describes three cases of advanced islet cell tumors treated effectively with radiotherapy. This experience, in addition to that from other published reports, suggests that radiotherapy is a useful mode for treating advanced islet cell carcinoma.     

Hyperprolactinaemia and sexual function in the male

Although an uncommon cause of sexual dysfunction, hyperprolactinaemia is almost invariably associated with loss of libido and impotence in men. The finding of hyperprolactinaemia should prompt a systematic search for an underlying cause, particularly prolactin-secreting pituitary adenomas; in this condition, sexual dysfunction may antedate other complications of the pituitary tumour by many years.     

The prevalence and intensity of intestinal parasites in two Somalian communities

About 85% of the population of two Somali communities harboured soil-transmitted intestinal nematodes and/or protozoa. The commonest parasite (75% in the Lafoole institution and 59% in the Afgoye institution) was Trichuris trichiura. Mixed infections were common. The source of infection is contaminated fields around dwelling quarters, because of indiscriminate defaecation. One of the factors responsible for the higher incidence of hookworm in Lafoole (45%) compared with Afgoye (1.5%) may be the different soil character of the surrounding fields.     

Curative local excision of rectal adenocarcinoma

The records of all 28 patients with rectal adenocarcinoma treated by potentially curative local excision by one surgeon (A.M.C.) between 1970 and 1984 were reviewed. Patient age, sex, tumour size, site, degree of differentiation and level of invasion are reported. The procedure was associated with no mortality and minimal morbidity. Twenty-two patients, followed for an average of 51 months, have either died of other causes or remain free of recurrent or disseminated malignancy. Six patients have required further surgery for local recurrence. Of these, one patient has had a repeat local excision while the remaining five patients have had an abdominoperineal excision of the rectum. All six patients, followed since the second operation for an average of 50 months, are free of further recurrent or disseminated disease. The results reported in this review suggest that in a selected group of patients with rectal adenocarcinoma curative local excision may offer a safe alternative to more radical forms of surgery.     

Therapeutic potential of choline magnesium trisalicylate as an alternative to aspirin for patients with bleeding tendencies

We have compared the effects of acetyl salicylic acid (ASA, aspirin) and choline magnesium trisalicylate (CMT), a non-acetylated salicylate product, on platelet aggregation in human whole blood ex-vivo. Using a whole blood platelet counter, platelet aggregation was quantified by measuring the fall in the number of single platelets at peak aggregation in response to collagen, arachidonic acid (AA), as well as spontaneous aggregation. In double blind and random order, 12 healthy volunteers received, on two separate occasions 10 days apart, a single oral dose of 652 mg ASA or 655 mg CMT. Despite a comparable absorption of salicylic acid from the two drugs, ingestion of ASA resulted in a marked inhibition of platelet aggregation induced by collagen (p less than 0.005), AA (p less than 0.01) and spontaneous aggregation (p less than 0.01), whereas such effects were not observed after CMT ingestion. We suggest that CMT may have therapeutic potential as an alternative to aspirin when inhibition of platelet aggregation can induce bleeding complications.     

Ileoanal reservoir for ulcerative colitis and familial polyposis

Although total proctocolectomy with permanent ileostomy is regarded as the definitive therapy for ulcerative colitis and familial polyposis, psychologic and physical complications with this operation have stimulated the development of the operation of total abdominal colectomy, mucosal proctectomy, ileal reservoir, and ileoanal anastomosis as an alternative surgical procedure. Since 1980, 104 of these operative procedures have been completed with no operative mortality; experience has been gained with both the J- and S-type reservoirs. Despite an appreciable number of postoperative complications, satisfactory function of the reservoir has been achieved in 86 of 91 patients followed up for at least three months after closure of the ileostomy. The remaining five patients have required reinstitution of fecal diversion. Functional results have not differed between two-limbed and three-limbed reservoirs. This operation must be considered a viable alternative in patients with ulcerative colitis and familial polyposis.