Hemoglobin M equon beta 41 (C7) phenylalanine leads to tyrosine

A severe hemolytic crisis was observed in a 34-yr-old female of English- Irish extraction following a viral illness treated with acetaminophen. Heinz bodies and heat instability were present only during a transient hemolytic event. A challenge dose of acetaminophen caused no detectable hematologic abnormality. Structural studies of the hemoglobin during hemolysis and again after complete recovery localized the abnormality to tryptic peptide beta Tp-5, and automated sequencing of I 125-labeled beta chains indicated a replacement of phenylalanine (C7) beta 41 by tyrosine. Substitution of the next residue, phenylalanine (CD1) beta 42 by serine (Hb Hammersmith), has resulted in chronic severe Heinz body hemolytic anemia. The lack of chronic anemia in the present disorder may reflect the different relationships of beta41 and beta 42 and/or the similarities in volume and hydrophobicity of tyrosine and phenylalanine. It is suggested that substitution of tyrosine for phenylalanine in Hb Mequon may disturb the critical environment around the heme group and render it susceptible to oxidative denaturation in the presence of infections and/or drugs.     

Effect of thermal shock on seed resistance

The work was performed in order to evaluate possible negative effect of high temperatures on biological properties of seeds in space experiment BIORISK-MSN-2. Laboratory experiments showed that seeds possess high enough resistance to extended exposure to high temperatures. Results of studying effects of positive temperatures in the region of 40 to 100 degrees C on biological properties of seeds of 19 species and varieties of higher plants belonging to three different families lead to the conclusion that heat stability of seeds depends on temperature value, period of exposure, species, variety and individual peculiarities of plants. These data can be useful in future interpretation of results of experiment BIORISK-MSN-2.     

Sarcomas in the groin and inguinal canal �C often missed and difficult to manage

INTRODUCTION

This is a 7-year retrospective review summarising the North of England Bone and Soft Tissue Tumour Service''s experience of managing 13 cases of groin sarcoma requiring soft tissue flap reconstruction. This study was performed to try to identify where national referral guidelines in sarcoma management had been followed and reasons for any delays. The study also includes outcome data relating to these patients.

PATIENTS AND METHODS

A retrospective, case-note review was undertaken using the local sarcoma database to identify approriate patients.

RESULTS

In nine patients, national referral guidelines were not followed. This resulted in a mean delay of presentation to the multidisciplinary team of 4.4 months. Ten patients had unplanned excision or exploration of tumours before referral. There were no lower limb amputations. All patients with narrow margins or high grade tumours were referred for radiotherapy. Four patients died; three as a result of distant metastases and one as a result of local recurrence.

CONCLUSIONS

Despite delays in referral, treatment by wide excision and plastic surgical reconstruction allowed for local control of these tumours with functional limb salvage. Implementation of National Institute for Health and Clinical Excellence (NICE) guidelines and local strategies could improve the expedient management of these patients.     

Autoerythrocyte sensitization syndrome (Gardner–Diamond syndrome): review of the literature**

A review of the literature concerning psychogenic purpura is presented. The diagnosis is usually based on typical anamnestic data, clinical presentation (painful inflammatory skin lesions, which progressed to ecchymoses during the next 24 h) and positive diagnostic tests with intracutaneous injections of 80% solution of washed autologous erythrocytes. No pathological findings of blood coagulation parameters are usually detected. Histopathological evaluations of lesional biopsies revealed non-specific changes. Taking into account the high frequency of psychic disorders and stress dependence of skin symptoms, therapy with psychotropic drugs (according to indications) and psychotherapy are pathogenetically grounded methods of treatment in psychogenic purpura, and should be provided together with symptomatic therapy.     

The natural history of factor VIII:C inhibitors in patients with hemophilia A: a national cooperative study. II. Observations on the initial development of factor VIII:C inhibitors

During a 4-year multicenter cooperative study of acquired factor VIII inhibitors in persons with hemophilia A, new inhibitors were detected in 31 of 1,306 patients who entered the study without an inhibitor or the history of an inhibitor. The incidence of new inhibitors was eight per 1,000 patient-years of observation. The factor VIII:C level before inhibitor development was less than or equal to 0.03 U/mL in 29 individuals and 0.06 U/mL and 0.07 U/mL in the remaining two. Factor VIII:Ag levels were measured in 27 individuals and were less than 0.03 U/mL in 23 and 0.05 to 0.11 U/mL in the remaining four. Maximum inhibitor levels ranged from 1.0 to 9,044 Bethesda U/mL. In seven patients under the age of 20, relatively weak inhibitors (none higher than 4.3 Bethesda U/mL) were detected on only a single occasion despite continued factor VIII challenge. In the other 24 patients with inhibitors detected on multiple occasions, 50% had appeared by age 20 and 71% by age 30. Seventeen of the 31 inhibitors, including 12 of 15 with maximum values greater than 10 Bethesda U/mL, developed within 75 exposure days to factor VIII.     

Parametric control of the yield characteristics and species composition dynamics of algal poly-culture]

There are several experimental models of biological life support systems (BLSS) designed to incorporate a chlorella pool. These BLSS can be optimized if populated by algal associations that could take up more functions within the closed cycling system than a single alga species. Introduction of a Spirulina and Chlamydomonas poly-culture with differing in gas exchange and biochemical composition resulted in a tighter closure of linkages within the system. The factors determining the size of a species population in intensive continuous poly-cultures are, first and foremost, pH and suspension flow rate. Experimental testing of this supposition brought us to the conclusion that parametric control of alga productivity and species composition dynamics makes it possible to create a steady intensive poly-culture as part of the LSS for humans. Flow rate and pH can be the parameters for control of the Spirulina and Chlamydomonas populations during continuous cultivation of this poly-culture.