Proliferative state of normal in vitro colony-forming cells during development of L5222 rat leukemia and their reaction to chemotherapy

In the experimental rat leukemia, L5222, the decrease of normal in vitro colony-forming cells (CFU-C) after chemotherapy with daunomycin is much less than in nonleukemic controls. The leukemia is therefore used here to test the hypothesis that in leukemia the CFU-C are expelled from the active cell cycle to a resting state and are thereby less sensitive to cycle-dependent chemotherapeutic agents. The L5222 leukemia has the advantage that the leukemic blast cells do not form colonies in agar culture so that normal CFU-C can be assessed under leukemic conditions. To compare the proportions of CFU-C in the S-phase in normal and leukemic rats, two S-phase-specific agents, 3H-thymidine and hydroxyurea, were used to kill proliferating bone marrow cells. Following treatment with 3H-thymidine in vitro, about 41% of the CFU-C were killed in normal and about 25% in leukemic bone marrow. Hydroxyurea administered in vivo resulted in the death of about 33% and 26%, respectively. The results indicate that fewer normal CFU-C are in S-phase in the L5222 leukemia, which might help to explain how enough normal stem cells survive chemotherapy to regenerate the bone marrow.     

Neutrophils do not bind to or phagocytize human immune complexes formed with influenza virus

Neutrophils appear to form the first line of defense against influenza virus, yet it is unclear how these leukocytes recognize influenza- infected cells. While demonstrating that neutrophils adhere specifically to the sialic acid-binding site on the hemagglutinin molecule (HA) on the surface of influenza-infected (WSN[H1N1]) epithelial cells and not to other viral or epithelial cell antigens, it was observed that human neutrophils do not recognize immune complexes formed with influenza virus. Intact antibodies (mouse monoclonal antibodies [MoAbs] IgG1 and IgG2b, human immune heat-inactivated serum [predominantly IgG1], and IgG purified from human immune serum) that block the sialic acid-binding site on HA significantly reduced (> 80%) neutrophil adherence to influenza-infected epithelial cells. Binding and phagocytosis of free influenza virions and neutrophil agglutination by influenza virus were completely prevented by these antibodies. Intact and F(ab')2 fragments of mouse MoAbs to other viral epitopes caused increased neutrophil adherence to infected cells. This binding was eliminated by F(ab'2) fragments of MoAbs against the sialic acid- binding site on HA, but not by saturating amounts of MoAbs, which block the neutrophil Fc receptors. Thus, it appears that human neutrophils show little ability to bind via their Fc receptors to the immune complexes formed with antibody and either influenza-infected epithelial cells or the free virion. These findings are in contrast to the general dogma, and are the first example of antibody opsonization reducing, rather than enhancing, neutrophil binding and phagocytosis of a pathogen.     

Sequence Analysis of the Second Internal Transcribed Spacer (ITS2) Region of rDNA for Species Identification of Trichostrongylus Nematodes Isolated From Domestic Livestock in Iran

Background

Infectivity of herbivores with Trichostrongylus nematodes is widespread in many countries, having a major economic impact on breeding, survivability, and productivity of domestic livestock. This study was carried out on Trichostrongylus species isolated from domestic livestock in order to develop an easy-to-perform method for species identification.

Methods

Trichostrongylus isolates were collected from sheep, goat, cattle, and buffaloes in Khuzestan Province, southwest Iran. Primary species identification was carried out based on morphological characterization of male worms. PCR amplification of ITS2-rDNA region was performed on genomic DNA and the products were sequenced. Phylogenetic analysis of the nucleotide sequence data was conducted employing Bayesian Inference approach. Consequently, a restriction fragment length polymorphism (RFLP) profile was designed to differentiate Trichostrongylus species.

Results

A consensus sequence of 238 nucleotides was deposited in the GenBank for Iranian isolates of Trichostrongylus species including T. colubriformis, T. capricola, T. probolurus and T. vitrinus. The designated RFLP using restriction enzyme TasI could readily differentiate among species having different ITS2 sequence. The molecular analysis was in concordance with morphological findings.

Conclusion

Phylogenetic analysis indicated a close relationship among the sequences obtained in this study and reference sequence of relevant species. ITS2-RFLP with TasI is recommended for molecular differentiation of common Trichostrongylus species.     

Incidence,and Gender,Age and Ethnic Distribution of Sarcomas in the Republic of Suriname from 1980 to 2008

Objective:

We report on the incidence and the gender, age and ethnic distribution of sarcomas diagnosed between 1980 and 2008 in the multi-ethnic Republic of Suriname.

Methods:

Total and average yearly number of cases, crude rates, as well as relevant population data were derived from the records of the Pathologic Anatomy Laboratory and the General Bureau of Statistics, respectively, and stratified according to gender, age groups 0–19, 20–49 and 50+ years, and the largest ethnic groups (Hindustani, Creole, Javanese and Maroons).

Results:

Between 1980 and 2008, 258 sarcomas were diagnosed in Suriname, ie at a frequency of nine per year and an annual rate of two per 100 000. Overall, there was 0.9 male per female, two to four cases per year in each age group, and one to three patients in each ethnic group. Soft-tissue sarcomas comprised approximately 80% of overall cases, with a male/female ratio that was approximately 0.5; almost 90% of patients were older than 20 years; more than one-third was Creole. Leiomyosarcoma, fibrosarcoma and liposarcoma were most frequently encountered (90 cases), particularly above 20 years of age, while leiomyosarcomas seemed, additionally, more common in women and Creoles or Maroons. The most numerous bone tumours were primitive neuroectodermal tumour/Ewing tumour and osteosarcoma (37 cases). They were more common in males, the youngest age group, and Hindustanis and Creoles.

Conclusions:

The incidence of sarcomas in Suriname, and their gender, age and ethnic distribution in general, seemed comparable with international data. The main exception might be leiomyosarcoma which might have a predilection for Afro-Surinamese.     

Red cell tolerance of admixture with heated saline

Red cell stability in the face of thermal stress has been evaluated only in the setting of prolonged incubation. This study was conducted to determine red cell tolerance of rapid mixture with heated saline, which exposes red cells to heat only until thermal equilibration, which is a matter of seconds. Half-units of 35-day-old red cells stored in CPDA-1 were mixed at 6 to 10 degrees C in the blood container with an equal weight of 60, 70, or 80 degrees C saline. This resulted in mean mixture temperatures of 30.9, 37.5, and 42.6 degrees C, respectively. Controls consisted of the same mixture, but with 6 to 10 degrees C saline. The red cells in the mixtures were assessed for osmotic fragility, and the supernatant was examined for plasma hemoglobin and potassium. Neither osmotic fragility curves nor supernatant hemoglobin or potassium changed significantly with saline temperatures of 60 or 70 degrees C. When 80 degrees C saline was used, osmotic fragility, supernatant hemoglobin, and potassium all increased significantly (p less than 0.01) over control values. Red cells tolerate rapid mixture with 70 degrees C saline without hemolysis or change in osmotic fragility.     

Oral Assessment and Nursing Interventions Among Nigerian Nurses-Knowledge,Practices and Educational Needs

Background

Assessment of oral condition, oral care, and informing the attending doctor of unusual oral findings for possible consultation or referral to a dentist are the advocated roles of hospital nurses. The objective of the study was thus to assess the roles of Nigerian nurses in the assessment of oral conditions of hospitalized patients.

Methods

This questionnaire-based cross-sectional survey of all nurses caring for hospitalized patients in the University of Benin Teaching Hospital was conducted in the first half of 2010.

Results

Of the 384 studied participants, 94.3% considered oral care as an important aspect of nursing care and 73.4% had oral health component in their nursing school curriculum. A total of 80.7% reported suspicious and abnormal findings in hospitalized patients to the attending doctor. Amongst the respondents, 38.0% reported ability to conduct good oral tissue examination. Only 28.1% demonstrated good knowledge of common oral diseases. Three-quarters (73.4%) thought that it is compulsory for nurses to assess the oral condition of hospitalized patients. The 67.7% and 21.9% of the respondents did the assessment on admission and discharge respectively. The majority (90.1%) desired training on oral care of hospitalized patients.

Conclusion

There is a need to improve the skill and competence of nurses in the assessment of oral condition to make them a substantive partner in the oral care of hospitalized patients.