Motor reflex responses elicited by cutaneous stimulation in the regenerating nerve of man: Axon reflex or ephaptic response?

In 57 of 60 nerves (29 median and 31 ulnar) sutured at the wrist, forearm and arm, we recorded motor responses in thenar or hypothenar muscles by electrical stimulation of the corresponding fingers. Recordings were made at different times during the process of regeneration, ranging from 3 months up to 11 years. The responses showed a constant shape and latency to every stimulation (simple or repetitive). The latency was shorter the more distal the level of injury and the greater the elapsed time from the reinnervation. The point of "reflexion" of the responses is at or very near the line of nerve suture. The electrophysiological behavior of the responses fits well with either the criterion of axon reflex or ephaptic response. We discuss both possibilities and conclude that it is not possible, with the electrophysiological technique that we used, to distinguish between an axon reflex and an ephaptic response.     

A case-control study of cytochrome P450 1A1, glutathione S-transferase M1, cigarette smoking and lung cancer susceptibility (Massachusetts, United States)

Cytochrome P450 1A1 (CYP1A1) and glutathione S-transferase M1 (GSTM1)genetic polymorphisms are involved in the activation and detoxification ofchemical carcinogens found in tobacco smoke; thus they may influence hostsusceptibility to lung cancer. In this study at Massachusetts GeneralHospital (Boston, MA, USA) of 416 cases and 446 controls (mostly White) weevaluated the association between the CYP1A1 MspI and GSTM1 polymorphisms andlung cancer risk, and their interaction with cigarette smoke. The CYP1A1 MspIheterozygous genotype was present in 18 percent of cases and 16 percent ofcontrols, and one percent of cases and controls were CYP1A1 MspI homozygousvariant. The GSTM1 null genotype was detected in 54 percent of cases and 52percent of controls. After adjusting for age, gender, pack-years of smoking,and years since quitting smoking, while neither the CYP1A1 MspI heterozygousgenotype alone nor the GSTM1 null genotype alone were associated with asignificant increas e in lung cancer risk, having both genetic traits wasassociated with a twofold increase in risk (95 percent confidence interval[CI] = 1.0-3.4). Our data did not provide enough evidence for a substantialmodification of the effect of pack-years on lung cancer risk by the CYP1A1MspI and GSTM1 genotypes. However, limitations of our study preclude aconclusion about this potential interaction.     

Outcomes and Costs of Risperidone versus Olanzapine in Patients with Chronic Schizophrenia or Schizoaffective Disorders: A Markov Model

OBJECTIVE: To compare expected outcomes and costs of care in patients with chronic schizophrenia or schizoaffective disorders who are treated with risperidone versus olanzapine. METHODS: A Markov model was developed to examine outcomes and costs of care in patients with chronic schizophrenia or schizoaffective disorders receiving risperidone or olanzapine. The time frame of interest was 1 year. The model focused particular attention on the likelihood of therapy switching and discontinuation as a result of treatment-emergent side effects, as the efficacy of these two agents is similar. Measures of interest included the incidence of relapse and selected side effects including extrapyramidal symptoms (EPS), prolactin-related disorders and diabetes, expected change in body weight, and the percentage of patients remaining on initial therapy at the end of 1 year. Costs of antipsychotic therapy and psychiatric and nonpsychiatric services also were examined. RESULTS: At 1 year, the rate of EPS was estimated to be slightly higher for risperidone, as was the incidence of symptomatic prolactin-related disorders. The expected incidence of diabetes mellitus, while low, was slightly higher for olanzapine. Approximately 25% and 4% of olanzapine and risperidone patients, respectively, were projected to experience an increase in body weight > or = 7%. The estimated percentage of patients remaining on initial therapy at the end of 1 year was higher for risperidone than olanzapine (76.9% vs. 45.6%, respectively). Expected mean total costs of care per month of therapy were $2163 for risperidone and $2316 for olanzapine. Results from sensitivity analyses suggest that the probability of therapy discontinuation following weight gain >5 kg would have to be lower than 0.1 for the number of patients remaining on therapy at the end of 1 year to be the same for risperidone and olanzapine. CONCLUSIONS: Compared with risperidone, treatment with olanzapine may result in greater increases in body weight, higher rates of therapy discontinuation, and higher costs of medical-care services.     

Allogeneic stem-cell transplantation may overcome the adverse prognosis of unmutated VH gene in patients with chronic lymphocytic leukemia.

PURPOSE: To investigate whether allogeneic stem-cell transplantation (allo-SCT) may overcome the negative impact of unmutated VH genes in the outcome of patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: We analyzed the outcome of patients who underwent SCT according to their VH mutational status. RESULTS: Thirty-four patients (14 allo-SCT and 20 autologous SCT [auto-SCT]) presented unmutated VH genes and 16 patients presented mutated VH genes (nine allo-SCT and seven auto-SCT). Tumoral burden pre-SCT was significantly higher in the allo-SCT patients independent of the VH mutational status. The risk of relapse was significantly higher after auto-SCT (5-year risk, 61%; 95% CI, 44% to 84%) than after allo-SCT (5-year risk 12%, 95% CI, 3% to 44%; P < .05). In the unmutated group, 13 of 20 auto-SCT and two of 14 allo-SCT patients experienced disease progression, with a risk of relapse at 5 years of 66% (95% CI, 48% to 93%) v 17% (95% CI, 5% to 60%), respectively (P = .01). CONCLUSION: These results show that allo-SCT may overcome the unfavorable effect of unmutated VH genes in patients with CLL.     

Role of the CDKN2A locus in patients with multiple primary melanomas.

PURPOSE: We have studied a consecutive case series of patients with multiple primary melanoma (MPM) for the involvement of the melanoma susceptibility loci CDKN2A and CDK4. PATIENTS AND METHODS: One hundred four MPM patients (81 patients with two primary melanomas, 14 with three, five with four, one with five, two with six, and one with seven) were included. RESULTS: Seven different CDKN2A germline mutations were identified in 17 patients (16.3%). In total, we identified 15 CDKN2A exon 2, one exon 1alpha missense mutation, and one exon 1beta frameshift mutation. The age of onset was significantly lower and the number of primary melanomas higher in patients with mutations. CDKN2A mutations were more frequent in patients with familial history of melanoma (35.5%) compared with patients without (8.2%), with a relative risk (RR) of 4.32 (95% CI, 1.76 to 10.64; P = .001), and in patients with more than two melanomas (39.1%) compared with patients with only two melanomas (10%) with an RR of 3.29 (95% CI, 1.7 to 6.3; P = .002). The A148T polymorphism was more frequent in patients with MPMs than in the control population (P = .05). A variant of uncertain significance, A127S, was also detected in one patient. No CDK4 mutations were identified, suggesting that it has a low impact in susceptibility to MPM. CONCLUSION: MPM patients are good candidates for CDKN2A mutational screening. These patients and some of their siblings should be included in a program of specific follow-up with total body photography and digital dermoscopy, which will result in the early detection of melanoma in this subset of high-risk patients and improve phenotypic characterization.     

Total esterase activity in human saliva: Validation of an automated assay,characterization and behaviour after physical stress

Although saliva has esterase activity, this activity has not been characterized or studied in individuals subjected to physical stress. The aim of this report was to develop and validate an automated spectrophotometric assay for total esterase activity measurement in human saliva, as well as to study the contribution of different enzymes on this activity and its behaviour under physical stress in healthy subjects. The assay used 4-nitrophenyl acetate as substrate and was precise, accurate and provided low limits of detection and quantification. Inhibition with diisopropylfluorophosphate showed that cholinesterase, carboxylesterase and cholesterol esterase contributions not represented more than 20% of total esterase. Addition of standards of lipase and albumin to saliva samples showed that both proteins significantly contributed to esterase activity only when equal or higher than 11.6?IU/L and 250?μg/mL, respectively. Western blot analyses showed absence of paraoxonase-1 and high amount of carbonic anhydrase-VI. The high affinity of purified carbonic anhydrase-VI for the substrate supported a major contribution of this enzyme. Total esterase activity and alpha-amylase was measured in saliva samples from 12 healthy male students before and after participation in an indoor football match. The activity significantly increased after match and positively correlated with salivary alpha-amylase. This method could be used as a biomarker of physical stress in humans, with carbonic anhydrase-VI being the esterase that contributed more to the activity of the assay.     

Energy density,diet quality,and central body fat in a nationwide survey of young Spaniards

ObjectivesTo determine the impact of energy density on diet quality and anthropometric proxy measures for central body fat in young Spaniards.MethodsData were obtained from a representative national sample of 2513 young Spaniards aged 10 to 24 y. Dietary assessment was performed with a 24-h recall. Adherence to the Mediterranean diet was measured by the KIDMED index. Reduced rank regression analysis was used to identify energy-density dietary patterns. Waist circumferences and height were measured.ResultsPastries and sausages showed the strongest loading for the dietary energy density factor score (DED-FS), with fruits and vegetables at the opposite end of the scale. Multiple linear regression analysis showed a positive association (P < 0.01) of dietary energy density (DED) and the DED-FS with waist circumferences regressed on height and age (WC_height+age) and waist-to-height ratio (WHtR). The adjusted odds ratio for elevated WC_height+age and WHtR increased across quartile distribution of DED (P < 0.001) and DED-FS (P < 0.05). Diet quality characterized by the KIDMED index was negatively associated (P < 0.001) with DED and the DED-FS.ConclusionsHigher DED is a risk for increased central fat distribution and is associated with low adherence to the Mediterranean diet.