Carbohydrate loading in human muscle: an improved 1 day protocol

It is generally acknowledged that even without a glycogen-depleting period of exercise, trained athletes can store maximal amounts of muscle glycogen if fed a carbohydrate-rich diet for 3 days. What has never been examined is whether under these conditions this many days are necessary for the content of muscle glycogen to attain these high levels. To examine this issue, eight endurance-trained male athletes were asked to eat 10 g.day(-1).kg(-1) body mass of high-carbohydrate foods having a high glycaemic index over 3 days, while remaining physically inactive. Muscle biopsies were taken prior to carbohydrate loading and after 1 and 3 days of eating the carbohydrate-rich diet. Muscle glycogen content increased significantly ( P<0.05) from pre-loading levels of [mean (SE)] 95 (5) to 180 (15) mmol.kg(-1) wet mass after only 1 day, and remained stable afterwards despite another 2 days of carbohydrate-rich diet. Densitometric analyses of muscle sections stained with periodic acid-Schiff not only supported these findings, but also indicated that only 1 day of high carbohydrate intake was required for glycogen stores to reach maximal levels in types I, IIa, and IIb muscle fibres. In conclusion, these findings showed that combining physical inactivity with a high intake of carbohydrate enables trained athletes to attain maximal muscle glycogen contents within only 24 h.

Rapid carbohydrate loading after a short bout of near maximal-intensity exercise

PURPOSE

One limitation shared by all published carbohydrate-loading regimens is that 2-6 d are required for the attainment of supranormal muscle glycogen levels. Because high rates of glycogen resynthesis are reported during recovery from exercise of near-maximal intensity and that these rates could in theory allow muscle to attain supranormal glycogen levels in less than 24 h, the purpose of this study was to examine whether a combination of a short bout of high-intensity exercise with 1 d of a high-carbohydrate intake offers the basis for an improved carbohydrate-loading regimen.

METHODS

Seven endurance-trained athletes cycled for 150 s at 130% VO2peak followed by 30 s of all-out cycling. During the following 24 h, each subject was asked to ingest 12 g.kg-1 of lean body mass (the equivalent of 10.3 g.kg-1 body mass) of high-carbohydrate foods with a high glycemic index.

RESULTS

Muscle glycogen increased from preloading levels (+/- SE) of 109.1 +/- 8.2 to 198.2 +/- 13.1 mmol.kg-1 wet weight within only 24 h, these levels being comparable to or higher than those reported by others over a 2- to 6-d regimen. Densitometric analysis of muscle sections stained with periodic acid-Schiff not only corroborated these findings but also indicated that after 24 h of high-carbohydrate intake, glycogen stores reached similar levels in Type I, IIa, and IIb muscle fibers.

CONCLUSION

This study shows that a combination of a short-term bout of high-intensity exercise followed by a high-carbohydrate intake enables athletes to attain supranormal muscle glycogen levels within only 24 h.

Assessment of psychological distress in prospective bone marrow transplant patients

Patient psychological distress is associated with many aspects of the bone marrow transplantation (BMT) process and has been linked with poor treatment outcomes. We assessed psychological distress in potential BMT candidates, and compared patient and nurse coordinator ratings of emotional distress at the time of initial BMT consultation. Fifty patients self-reported psychological distress using both the NCCN Distress Thermometer (DT) and the Hospital Anxiety and Depression Scale (HADS). Coordinators rated patient emotional distress using the DT and Coordinator Rating Scales that measure anxiety and depression. Fifty and 51% of patients self-reported clinically significant levels of emotional distress and anxiety, respectively, but only 20% self-reported clinically significant levels of depression. There was good correlation between ratings using the brief DT and the more comprehensive HADS. There was significant but only moderate agreement between patient and coordinator ratings of emotional distress and anxiety, with coordinators underestimating the number of patients with high levels of emotional distress. In addition, coordinator ratings of patient emotional distress primarily reflected anxiety, whereas anxiety and depression together only minimally accounted for patient self-reports of psychological distress. These findings suggest that: (1) the DT can be a useful screening device; (2) approximately half of patients at the time of initial consultation for BMT already experience significant levels of psychological distress; and (3) coordinators observe emotional distress primarily as anxiety, but patients experience psychological distress as something more than anxiety and depression.

Immunosuppressed surfactant protein A-deficient mice have increased susceptibility to Pneumocystis carinii infection

Immunosuppressed Swiss Black mice deficient in surfactant protein A (SP-A(-/-)) and wild-type control mice (SP-A(+/+)) were exposed to Pneumocystis carinii by environmental exposure, intratracheal inoculation, and direct exposure to other infected animals. The frequency and intensity of P. carinii infection were significantly greater in the SP-A(-/-) mice by all 3 methods of exposure. P. carinii free of SP-A and alveolar macrophages were isolated from SP-A(-/-) mice and were tested in an in vitro attachment assay. Pretreatment of P. carinii with human SP-A resulted in a significant dose-dependent increase of the adherence of P. carinii to the macrophages. Thus, SP-A plays a role in host defense against P. carinii in vivo, perhaps by functioning as a nonimmune opsonin.

Blastic transformation of splenic marginal zone B-cell lymphoma

To our knowledge, blastic transformation of splenic marginal zone lymphoma, a recently characterized low-grade lymphoproliferative disorder, has not been reported previously. In this regard, we report the unique case of a 70-year-old woman whose untreated splenic marginal zone lymphoma underwent blastic transformation 3 years after diagnosis. Her hematologic medical history started in 1988 as thrombocytopenia refractory to steroids associated with atypical lymphoid infiltrate in the bone marrow. She underwent splenectomy in 1989, which revealed splenic marginal zone lymphoma. One year later, the patient developed lymphadenopathy noted in the chest, axillary, abdominal, and retroperitoneal lymph nodes. Because she was asymptomatic, treatment was limited to a conservative supportive regimen. The nodal lymphoma cells had features associated with marginal zone lymphoma and expressed B-cell monotypic kappa light chain. She was readmitted for the last time 2 years later with findings of 16% blasts in the peripheral blood and massive infiltration of the bone marrow by large blastoid cells. The blasts showed dispersed chromatin and prominent nucleoli, and possessed a moderate amount of clear cytoplasm. The blasts, like the previous nodal and splenic lymphomas, had a CD20-, CD19-, IgM-positive phenotype, but lacked reactivity for CD5, CD10, and CD23. The patient displayed clinical remission after treatment with vincristine and prednisone, but died of aspiration pneumonia 1 month later. These observations suggest that, similar to the other low-grade lymphoproliferative disorders, an untreated splenic marginal zone lymphoma may undergo high-grade blastic transformation.

National Heart Attack Alert Program position paper: chest pain centers and programs for the evaluation of acute cardiac ischemia

The National Heart Attack Alert Program (NHAAP), which is coordinated by the National Heart, Lung, and Blood Institute (NHLBI), promotes the early detection and optimal treatment of patients with acute myocardial infarction and other acute coronary ischemic syndromes. The NHAAP, having observed the development and growth of chest pain centers in emergency departments with special interest, created a task force to evaluate such centers and make recommendations pertaining to the management of patients with acute cardiac ischemia. This position paper offers recommendations to assist emergency physicians in EDs, including those with chest pain centers, in providing comprehensive care for patients with acute cardiac ischemia.

Multilobated large B-cell lymphoma diagnosed cytologically. A case report

BACKGROUND

Fine needle aspiration (FNA) biopsy can be used to reliably classify most conditions involving lymph nodes or, at least, significantly reduce the differential diagnosis.

CASE

A 70-year-old male presented with an ulcerated mass arising from the left tonsillar fossa and involving the anterior and posterior pillars. A biopsy of the tonsillar mass performed at an outside hospital was interpreted as a large cell undifferentiated carcinoma. Subsequently the patient developed systemic lymphadenopathy. A bone scan showed intense uptake within the medial tibial plateau of the left knee. FNA biopsy of the right axillary mass was interpreted at University of Cincinnati Medical College as a large cell lymphoma, multilobated type. Histologic and immunohistochemical studies of the lymph node confirmed the presence of multilobated B-cell lymphoma. Lymphoma chemotherapy was initially successful but was discontinued due to toxicity. The patient died two months after the initial cytologic diagnosis of lymphoma.

CONCLUSION

Multilobated lymphomas are an unusual variant of non-Hodgkin's lymphomas (mostly B-cell type). Cytology and immunocytochemistry are useful diagnostic procedures that can help to diagnose this relatively uncommon type of lymphoma and significantly reduce the possibility of misdiagnosis.

Occupational exposure to antineoplastic agents: self-reported miscarriages and stillbirths among nurses and pharmacists

Insult to the germ cells of an ovum or sperm prior to pregnancy as well as exposures to a fetus during pregnancy can affect the outcome of a pregnancy. Antineoplastic agents are mutagenic and teratogenic, so the potential effects of exposure on reproduction are of concern to the workers who handle them. This study investigates pregnancy loss associated with occupational exposures to antineoplastic drugs by comparing rates of spontaneous abortion and stillbirths for pregnancies without antineoplastic exposure and exposed pregnancies in which the pregnant woman or the father handled antineoplastic agents either before or during the pregnancy. A total of 7094 pregnancies of 2976 pharmacy and nursing staff were examined. After age during pregnancy, prior gravidity, maternal smoking during the pregnancy, and occurrence of a spontaneous abortion or stillbirth in a prior pregnancy were controlled for, exposure of the mother to or the handling of antineoplastic agents during the pregnancy was associated with a significantly increased risk of spontaneous abortion (odds ratio = 1.5; 95% confidence interval, 1.2 to 1.8) and combined risk of spontaneous abortion and stillbirth (odds ratio = 1.4; 95% confidence interval, 1.2 to 1.7) but not stillbirth alone. Among the wives of exposed men, too few stillbirths occurred to allow analysis. However, for spontaneous abortion and any loss, the patterns of increased risk were similar to those seen for women, although the odds ratios were not statistically significant.

Cost of malaria control in Sri Lanka

The study provides estimates of the cost of various malaria control measures in an area of North-Central Province of Sri Lanka where the disease is endemic. We assumed that each measure was equally effective. In these terms, impregnating privately purchased bednets with insecticide was estimated to cost Rs 48 (US(40.87) per individual protected per year, less than half the cost of spraying houses with residual insecticides. Larviciding of vector breeding sites and especially the elimination of breeding habitats by flushing streams through seasonal release of water from upstream reservoirs was estimated to be cheaper than other preventive measures (Rs 27 (US$ 0.49) and Rs 13 (US$ 0.24) per individual protected, respectively). Inclusion of both operational and capital costs of treatment indicates that the most cost-effective intervention for the government was a centrally located hospital with a relatively large catchment area (Rs 71 (US$ 1.29) per malaria case treated). Mobile clinics (Rs 153 (US$ 2.78) per malaria case treated) and a village treatment centre (Rs 112 (US$ 2.04)) per malaria case treated) were more expensive options for the government, but were considerably cheaper for households than the traditional hospital facilities. This information can guide health planners and government decision-makers in choosing the most appropriate combination of curative and preventive measures to control malaria. However, the option that is cheapest for the government may not be so for the householders, and further studies are needed to estimate the effectiveness of the various preventive measures.