Oxidative metabolism of the human eosinophil

We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.     

Characterization of N-acetyltransferase 1 and 2 polymorphisms and haplotype analysis for inflammatory bowel disease and sporadic colorectal carcinoma

Background  

N-acetyltransferase 1 (NAT1) and 2 (NAT2) are polymorphic isoenzymes responsible for the metabolism of numerous drugs and carcinogens. Acetylation catalyzed by NAT1 and NAT2 are important in metabolic activation of arylamines to electrophilic intermediates that initiate carcinogenesis. Inflammatory bowel diseases (IBD) consist of Crohn's disease (CD) and ulcerative colitis (UC), both are associated with increased colorectal cancer (CRC) risk. We hypothesized that NAT1 and/or NAT2 polymorphisms contribute to the increased cancer evident in IBD.     

The cholinomimetic agent carbachol induces headache in healthy subjects

The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (V_MCA) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P  = 0.042) and in the postinfusion period (30–90 min) ( P  = 0.027). Carbachol infusion caused a drop in V_MCA ( P  = 0.003) and an increase in STA diameter ( P  = 0.006), but no increase in the RA diameter ( P  = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects.     

Variability in muscle size and strength gain after unilateral resistance training

PURPOSE: This study assessed variability in muscle size and strength changes in a large cohort of men and women after a unilateral resistance training program in the elbow flexors. A secondary purpose was to assess sex differences in size and strength changes after training. METHODS: Five hundred eighty-five subjects (342 women, 243 men) were tested at one of eight study centers. Isometric (MVC) and dynamic strength (one-repetition maximum (1RM)) of the elbow flexor muscles of each arm and magnetic resonance imaging (MRI) of the biceps brachii (to determine cross-sectional area (CSA)) were assessed before and after 12 wk of progressive dynamic resistance training of the nondominant arm. RESULTS: Size changes ranged from -2 to +59% (-0.4 to +13.6 cm), 1RM strength gains ranged from 0 to +250% (0 to +10.2 kg), and MVC changes ranged from -32 to +149% (-15.9 to +52.6 kg). Coefficients of variation were 0.48 and 0.51 for changes in CSA (P = 0.44), 1.07 and 0.89 for changes in MVC (P < 0.01), and 0.55 and 0.59 for changes in CSA (P < 0.01) in men and women, respectively. Men experienced 2.5% greater gains for CSA (P < 0.01) compared with women. Despite greater absolute gains in men, relative increases in strength measures were greater in women versus men (P < 0.05). CONCLUSION: Men and women exhibit wide ranges of response to resistance training, with some subjects showing little to no gain, and others showing profound changes, increasing size by over 10 cm and doubling their strength. Men had only a slight advantage in relative size gains compared with women, whereas women outpaced men considerably in relative gains in strength.     

An outbreak of food poisoning in a military establishment

Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.     

Association between palmoplantar pustulosis and cigarette smoking in Brazil: a case–control study

Background  Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives  To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods  Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results  Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions  There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established.