Regional radiotherapy as adjuvant treatment for head and neck malignant melanoma. Preliminary results

From 1983 through 1988, 83 patients with high-risk cutaneous malignant melanoma (primary lesion thicker than 1.5 mm or palpable lymphadenopathy) of the head and neck region were enrolled in a study designed to assess the efficacy of a few large doses of radiation (24 to 30 Gy in 4 to 5 fractions). The actuarial 2-year locoregional control rates for the three groups were 95%, 90%, and 83%, respectively. Corresponding survival rates were 80%, 71%, and 69%. The majority of failures were due to distant metastases. Locoregional control rates were better than those reported earlier with surgery alone for comparable patients. The treatment morbidity was minimal.     

Nurses' assessment of pain in surgical patients

AIM: This paper reports a study to compare nurses' ratings of pain intensity and suffering (affect) in adult surgical patients with patients' own ratings of these variables, and to investigate whether pain ratings were influenced by cultural and ethnic differences. BACKGROUND: Studies show that postoperative pain continues to be under-treated in a large proportion of cases. The problem may be partly due to inaccurate pain assessment by nurses. METHOD: A convenience sample of 95 patients and 95 nurses in adult surgical units was selected from four hospitals in Jerusalem, Israel in 2003-2004. A questionnaire was administered to each patient by the researcher. The questionnaire included: (a) a Hebrew translation of the Short-Form McGill Pain Questionnaire for pain sensation, pain affect, and present pain intensity at rest and on movement; (b) visual analogue scales for overall pain intensity, suffering, and satisfaction with treatment; and (c) demographic and cultural data. Within a few minutes of the patient completing the questionnaire, a nurse who had been allocated to care for that patient made an independent assessment of the patient's pain. The nurse then left the patient's room and filled in the same questionnaire. FINDINGS: Nurses significantly underestimated all dimensions of pain on the above scales, but accurately assessed patient treatment satisfaction. There were no statistically significant effects for cultural and ethnic differences in pain assessment. Both types of clinical area where nurses worked and nurses' level of nursing education were found not to influence their assessment. CONCLUSION: The findings have implications for the management of postoperative pain by highlighting the need for more accurate pain assessment. Further research is required to elucidate the way in which nurses and patients conceptualize pain and to understand better the process of pain assessment in clinical nursing practice.     

NADPH-d/NOS reactivity in the lumbar dorsal horn of congenitally hypothyroid pups before and after formalin pain induction

We have previously demonstrated that congenitally hypothyroid rat pups exhibit altered behavioral response to formalin pain induction during postnatal period. In the present study, using NADPH-diaphorase histochemistry and NOS immunostaining, we investigated the effect of congenital hypothyroidism on the NOS expression in spinal cord of intact neonates at postnatal days of 15 and 21. We also examined the effect of thyroid dysfunction on the NADPH-d/NOS expression in response to formalin nociception. Congenital hypothyroidism induced by propylthiouracil (PTU) treatment started from gestational day 16 and continued to postnatal day 15 or 21. Congenitally hypothyroid pups exhibited marked reduction in NADPH-d reactive cells (84% and 66% in P15 and P21, respectively; P < 0.001) and NOS-ir cells (52% and 91% in P15 and P21, respectively; P < 0.001) in superficial lumbar dorsal horn laminae (I–II) as compared to that of normal pups. Moreover, in congenitally hypothyroid pups the NADPH-d/NOS expression following hindpaw formalin injection did not change significantly. Our results demonstrate that congenital hypothyroidism affect developmental expression of NOS in spinal dorsal horn, which may in part explain the altered behavioral pain response as we previously reported in hypothyroid pups.     

Post-spike excitability indicates changes in membrane potential of isolated C-fibers

Recording of action potentials from single unmyelinated nerve fibers by microneurography is an important tool to investigate peripheral neural functions in human neuropathies. However, the interpretation of microneurography recordings can be difficult because axonal membrane potential is not revealed by this method. We tested the hypothesis that the recovery cycle of excitability after a single action potential is correlated with changes in the axonal membrane potential. To this end, we used the threshold tracking technique to study how different chemical mediators, with known effects on the membrane potential, influence the post-spike superexcitability of C-fiber compound action potentials in isolated rat sural and vagus nerves. We found that: (1) some chemical mediators (e.g., adenosine 5'-triphosphate) produce a reduction or loss of superexcitability together with increased axonal excitability, indicating membrane depolarization; (2) blockade of axonal hyperpolarization-activated (Ih) currents produces an enhancement of superexcitability together with a decreased excitability, indicating membrane hyperpolarization; and (3) application of calcium produces an increase in membrane threshold without an alteration in superexcitability, indicating a non-specific increase in surface charge and a change in the voltage-dependent activation of sodium channels. In addition, we demonstrated that membrane depolarization and hyperpolarization induce opposite post-spike latency shifts (changes in supernormality) in rat and human nerve segments. Thus, recordings of post-spike excitability and shifts in latency are sensitive techniques for detection of various types of neuromodulation, which are correlated with changes in membrane potential of unmyelinated peripheral axons and may help to understand observations obtained by microneurography in peripheral human neuropathies.     

Pain hypersensitivity in rats with experimental autoimmune neuritis, an animal model of human inflammatory demyelinating neuropathy

Experimental autoimmune neuritis (EAN) is a T cell mediated autoimmune disease of the peripheral nervous system that serves as an animal model of the acute inflammatory demyelinating polyradiculoneuropathy in Guillain-Barre syndrome (GBS). Although pain is a common symptom of GBS occurring in 55-85% of cases, it is often overlooked and the underlying mechanisms are poorly understood. Here we examined whether animals with EAN exhibit signs of neuropathic pain including hyperalgesia and allodynia, and assessed their peripheral nerve autoimmune inflammation. We immunized Lewis rats with peripheral myelin P2 peptide (amino acids 57-81) emulsified with complete Freund's adjuvant, or with adjuvant only as control. P2-immunized rats developed mild to modest monophasic EAN with disease onset at day 8, peak at days 15-17, and full recovery by day 28 following immunization. Rats with EAN showed a significant decrease in withdrawal latency to thermal stimuli and withdrawal threshold to mechanical stimuli, in both hindpaws and forepaws, during the course of the disease. We observed a significant infiltration of T cells bearing alphabeta receptors, and a significant increase in antigen-presenting cells expressing MHC class II as well as macrophages, in EAN-affected rats. Our results demonstrate that animals with active EAN develop significant thermal hyperalgesia and mechanical allodynia, accompanied by pronounced autoimmune inflammation in peripheral nerves. These findings suggest that EAN is a useful model for the pain seen in many GBS patients, and may facilitate study of neuroimmune mechanisms underlying pain in autoimmune neuropathies.     

The utility of capsule endoscopy in the diagnosis of Crohn's disease based on patient's symptoms

BACKGROUND AND GOALS: Video capsule endoscopy (VCE) enables visualization of the entire small bowel and can identify lesions that may go undetected by conventional endoscopy and radiography. In this study, we assessed whether patient's selection based on symptoms may increase the yield of VCE in the diagnosis of Crohn's disease (CD). STUDY: Findings of 125 consecutive patients referred for VCE in whom CD may be suspected, were analyzed. Indications for VCE included iron-deficiency anemia, abdominal pain, diarrhea, or a combination of symptoms. Capsule endoscopy (CE) results were defined positive if 4 or more obvious clear ulcers, erosions, or a region with clear exudate and mucosal hyperemia and edema were identified. RESULTS: One hundred twelve patients were included in the final analysis. Mean age of patients was 44+/-22 years and median follow-up 36+/-15 months. Findings on CE were considered compatible with a diagnosis of CD in 7 patients (6%). In general, CE yielded a diagnosis of CD in a very small portion of the patients (0% to 4%), except in patients undergoing the test for a combination of abdominal pain and diarrhea. In this group, findings suggestive of inflammatory bowel disease were encountered in one-third of the patients (P=0.002). CONCLUSIONS: The greatest yield of CE in diagnosing CD is achieved in young patients who present with symptoms of abdominal pain plus diarrhea.