[Mechanisms of chronification and potential addiction in tumor pain : Comparison with non-tumor pain - A review of the literature]. / Chronifizierungsmechanismen und Abhängigkeitspotenziale bei Tumorschmerz : Vergleich mit Nichttumorschmerz ­ eine Literaturübersicht.

BACKGROUND: Due to advances in oncological therapy options and increasing survival rates, the number of cancer patients with persistant pain, who are in need of analgesic therapy has increased. It has been proven that biopsychosocial mechanisms exist in patients with persistant non-cancer pain leading to chronification. Furthermore, addiction has been identified as a complication of analgesic therapy. OBJECTIVE: Can the multidimensional model of chronic pain enhancement and chronification be used for patients with cancer pain, analogue to patients with non-cancer pain? Can addiction sydromes as a result of analgesic treatment be demonstrated? MATERIAL AND METHODS: In this non-systematic review, a literature search was carried out for somatic and psychosocial chronification mechanisms in patients with cancer pain. Indications for potential addiction syndromes in cancer patients are demonstrated based on selected publications. A Medline search provided a number of relevant publications that are listed (see Supplementary Material). RESULTS AND DISCUSSION: Somatic chronification mechanisms, such as pain intensity, repetitive algesic stimuli, topical and demographic factors, are found both in persistant non-cancer pain and cancer pain. Cancer-induced peripheral and central sensitization mechanisms that can be due to underlying genetic variations, are specific for cancer pain. With regard to psychosocial determinants for pain chronification, both cancer and non-cancer patients show similar patterns. Furthermore, data from the literature support the existence of addiction in cancer patients. CONCLUSION: In order to optimize treatment more attention should be paid to the risk of chronification and addiction in cases of chronic persistant cancer pain.

CRPS I following artificial disc surgery: case report and review of the literature.

We report a case of type 1 complex regional pain syndrome (CRPS I) of the left leg following the implantation of an artificial disc type in the L4/5 segment of the lumbar spine using a midline left-sided retroperitoneal approach. This approach included the mobilisation of the sympathetic trunk with incision and resection of the intervertebral disc. The perioperative and immediate postoperative periods were uneventful, but on the second postoperative day the patient complained of a progressive allodynia of the whole left leg in combination with weakness of the limb. Neurological examination did not reveal any radicular deficit or paresis. A sympathetic reaction following the mobilisation of the sympathetic trunk during the ventral preparation of the spine was suspected and investigated further. A diagnosis of CRPS I was proposed, and the patient was treated with analgesia, co-analgesics for pain alienation, and systemic corticosteroid therapy. A computed tomography-guided sympathetic block and lymphatic drainage were performed. Following conservative orthopaedic rehabilitation therapy, the degree of pain, allodynia, weakness, and swelling were reduced and the condition of the patient was ameliorated. The cost-benefit ratio of spinal arthroplasty is still controversial. The utility of this paper is to debate a possible cause of a painful complication, which can invalidate the results of a successful operation.

Norepinephrine and phenylephrine effects on right ventricular function in experimental canine pulmonary embolism.

In a canine model of pulmonary embolism (PE) produced by infusion of autologous blood clots, mean arterial blood pressure (MAP) decreased to 73 +/- 4 mm Hg while cardiac output (CO) decreased to less than 50 percent of baseline. Intravenous infusion of phenylephrine (PHEN) and norepinephrine (NE) restored MAP to somewhat above baseline values. However, only NE restored CO to control levels. The right ventricular myocardial blood flow increased 15 percent in the PE group with PHEN and 229 percent with NE at equipressor concentrations. The right ventricular myocardial oxygen consumption (RVMVo2) was not significantly different between PE and PE + PHEN while PE + NE increased RVMVO2 by 144 percent to 20.2 +/- 1.8 ml/min/100 g. The RV output was not adequately restored with PE, but when RV contractility was augmented with NE, RV output was restored to baseline. Right ventricular minute work increased 100 percent with NE and was maintained with a 100 percent increase in oxygen consumption. Calculated pulmonary vascular resistance (PVR) was decreased during PE by 36 percent with PE + PHEN while PVR in NE-treated dogs decreased by 59 percent. In NE-treated animals, systemic vascular resistance (SVR) was restored to control levels while in PHEN-treated animals SVR increased about 75 percent from baseline. We conclude that the salutary effects of NE on RV output are due to both alpha and beta receptor stimulation, which increased contractility, RVMBF, and RVMVo2, and decreased both PVR and SVR. In the PHEN-treated dogs, our indices of minute-work, RVMBF, and RVMVo2 suggest that coronary autoregulation was intact; however, there was no apparent benefit to RV output. This study suggests that in the clinical setting of acute PE, the judicious use of NE, rather than PHEN, may be more beneficial in restoring RV function and systemic hemodynamics.

Antibodies in the sera of Mycoplasma pneumoniae-infected patients against proteins of Mycoplasma genitalium and other mycoplasmas of man.

Frequency and pattern of anti-Mycoplasma genitalium antibodies in sera of 50 patients with Mycoplasma pneumoniae-infection were examined by the Western immunoblot method. The sera reacted with several proteins of M. genitalium. However, during the course of infection there was only a moderate increase of antibodies mainly against the bands of 135 and 105 kd in contrast to the more intense increase of numerous bands of M. pneumoniae. If antibodies against the 168 kd-adhesin of M. pneumoniae were isolated by affinity chromatography, only the IgG-, but not the IgM-fraction reacted with the 135 kd protein of M. genitalium. Results with rabbit antisera supported these findings, additionally indicating a lack of substantial cross reactions between M. pneumoniae and other species except M. genitalium. The development of anti M. genitalium antibodies at early age and their relatively constant pattern suggest an early immunization by so far unknown cross reacting microbial antigens. Antigenic cross reactions between proteins of M. pneumoniae and M. genitalium apparently do not play a substantial role in the diagnostic serology of M. pneumoniae disease.

Use of adherence protein of Mycoplasma pneumoniae as antigen for enzyme-linked immunosorbent assay (ELISA).

Antibodies against the adherence protein of Mycoplasma pneumoniae are regularly found in patients with M. pneumoniae infection. Therefore, this 168-kilodalton (kDa) protein was used as an antigen in a dot-ELISA for serological diagnosis of M. pneumoniae disease. M. pneumoniae proteins were separated by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), gels were stained with Coomassie Blue, and the 168-kDa protein band was cut out and eluted using a special electroelution device. Isolated proteins or sonicated whole-cell antigens, respectively, were immobilized on a 96-well filtration plate with a nitrocellulose bottom (dot-ELISA). The test procedure was performed as in conventional ELISA tests, using alkaline phosphatase-labeled antihuman IgM or IgG antibodies, respectively, to detect antigen-antibody complexes. All results were confirmed by immunoblotting. The dot-ELISA using the 168-kDa antigen proved to be sensitive and specific. The specificity was tested on 53 sera of M. pneumoniae infections and on 490 serum specimens of patients with other respiratory diseases due to other pathogens, or with clinical conditions such as pancreatitis, meningitis or endocarditis. With regard to IgM antibodies, no false-positive reactions were found in non-M. pneumoniae diseases against the 168-kDa antigen, but there were such reactions against other M. pneumoniae proteins in immunoblots.

Amplified reflection in degenerate four-wave mixing: a more-accurate theory.

We report a theory of amplified reflection in degenerate four-wave mixing that includes Gaussian distribution of intensity in the incoming beams and different intensities for the two pumping beams. In the Kerr limit, we obtain an analytical solution that may explain previous experimental observations.