A quantitative assessment of the morphological characteristics of BeWo cells as an in vitro model of human trophoblast cells / Una evaluación cuantitativa de las características morfológicas de las células BeWo como un modelo in vitro de las células de trofoblasto humano

In order to study the detailed morphology of trophoblast cells during human implantation, BeWo cells were cultured as spheroids in suspension culture. These cultures were then processed for light and electron microscopical examination. The present study showed that the BeWo spheroids consist of two cell types which are cytotrophoblast-like and syncytiotrophoblast-like. The cells with larger nuclear diameter made up only about 1 percent of the cell population and appear to be those of syncytiotrophoblast. Therefore the predominant cell type of the BeWo spheroids appeared to be relatively undifferentiated and cytotrophoblast-like. About 10 percent of the BeWo cells in the present study were mitotic, indicating a highly proliferative population. Total cell number increased about 12 times during the culture period from 107 +/- 9 on day 1 to 1211 +/- 145 on day 7 whereas the volume per cell increased about 2 times, from 1300 um3 on day 1 to 2400 um3 on day 7. Therefore overall growth of BeWo spheroids is due to both hyperplasia and hypertrophy. However, it appears that cell proliferation outstrips volumetric growth. These quantitative data show that BeWo cells grow mainly by hyperplasia and provide baseline values for further studies. In addition, the results show that BeWo cell morphology has marked similarities to that reported for human trophoblast, making it a useful model for subsequent in vitro studies.

En un cultivo de suspensión se estudió la morfología de las células durante la implantación del trofoblasto humano, células BeWo. Estos cultivos fueron procesados y examinados a través de microscopía de luz y electrónica. El estudio mostró que los esferoides BeWo constan de dos tipos de células, citotrofoblasto y sincitiotrofoblasto. Las células con mayor diámetro nuclear parecen ser los sincitiotrofoblasto que representaban sólo el 1 por ciento de la población celular. Por tanto, el tipo celular predominante de los esferoides BeWo parecían ser relativamente indiferenciados como citotrofoblasto. Alrededor del 10 por ciento de las células BeWo fueron mitóticas, lo que indica una población altamente proliferativa. El número de células totales aumentó alrededor de 12 veces durante el período de cultivo de 107 +/- 9 días en el día 1 a 1211 +/- 145 en el día 7, mientras que el volumen de la célula creció alrededor de 2 veces, desde 1300 mm3 el día 1 hasta 2400 mm3 el día 7. Por lo tanto, el crecimiento global de esferoides BeWo se debe tanto a la hiperplasia como a la hipertrofia. Sin embargo, parece que la proliferación celular supera al crecimiento volumétrico. Estos datos cuantitativos muestran que las células BeWo crecen principalmente por hiperplasia y proporcionan valores de referencia para estudios posteriores. Además, los resultados muestran que la morfología celular BeWo ha marcado similitudes con los reportado para el trofoblasto humano, por lo que es un modelo útil para posteriores estudios in vitro.

Using mortuary statistics in the development of an injury surveillance system in Ghana.

OBJECTIVE: To develop, in a mortuary setting, a pilot programme for improving the accuracy of records of deaths caused by injury. METHODS: The recording of injury-related deaths was upgraded at the mortuary of the Komfo Anokye Teaching Hospital, Kumasi, Ghana, in 1996 through the creation of a prospectively gathered database. FINDINGS: There was an increase in the number of deaths reported annually as attributable to injury from 72 before 1995 to 633 in 1996-99. Injuries accounted for 8.6% of all deaths recorded in the mortuary and for 12% of deaths in the age range 15-59 years; 80% of deaths caused by injury occurred outside the hospital and thus would not have been indicated in hospital statistics; 88% of injury-related deaths were associated with transport, and 50% of these involved injuries to pedestrians. CONCLUSIONS: Injury was a significant cause of mortality in this urban African setting, especially among adults of working age. The reporting of injury-related deaths in a mortuary was made more complete and accurate by means of simple inexpensive methods. This source of data could make a significant contribution to an injury surveillance system, along with hospital records and police accident reports.

The African AIDS case definition and HIV serology in medical in-patients at Komfo Anokye Teaching Hospital, Kumasi, Ghana.

In 914 consecutive medical admissions to Komfo Anokye Teaching Hospital, the prevalence of infection with Human Immunodeficiency Virus type I (HIV-I) and Human Immunodeficiency Virus type 2 (HIV-2) was 12.6%. The prevalence in females was twice that found in males. The infection rate was maximum in the age group 25-29 years for females (45%) and 30-34 years for males (29%). There were 7 cases infected with HIV-2 alone, 55 cases infected with HIV-I alone and 53 cases with dual infection. The cases with HIV-2 infection tended to be older than those with HIV-I infection. For detecting HIV seropositivity in our patients the World Health Organization recommended case definition for AIDS in Africa gave a sensitivity of 32%, a specificity of 93% and a positive predictive value of 42%. The case definition gave the highest specificity and positive predictive values when cases of tuberculosis were not included in the analysis.

PIP: During November 1989-January 1990 in Ghana, medical officers clinically examined and took blood samples from 914 consecutive admissions to Komfo Anokye Teaching Hospital in Kumasi to determine seroprevalence of HIV and different clinical features of HIV infection as well as to assess the value of the World Health Organization (WHO) clinical case definition for AIDS. 12.6% of the admissions were infected with HIV-1 and/or HIV-2. Females were more than two times likely to be infected with HIV than males (17.6% vs. 8.8%). Overall, 25-29 year old women had the highest HIV infection rate (45%). 30-34 year old men had the highest HIV infection rate among males. 56.5% of HIV-infected females and 30.4% of HIV-infected males were infected with both HIV-1 and HIV-2. 7 cases (5 females and 2 males) were infected with just HIV-2. Their ages ranged from 35 to 75 years. When the researchers applied the WHO clinical case definition to all HIV seropositive cases, they found its sensitivity to be 32%, specificity to be 93%, and positive predictive value to be 42%. Sputum-positive tuberculosis (TB) accounted for much of the false positives (28/53). 15% of the 76 sputum positive TB cases were HIV infected. When the researchers excluded all confirmed or suspected TB cases from the analysis, the specificity and positive predictive value increased to a maximum of 97% and 61%, respectively; sensitivity was 28%. Many HIV seropositive cases were not diagnosed with HIV infection either by the case definition or clinically by ward physicians. They probably were asymptomatic. Clinicians should suspect patients diagnosed with pneumonia or meningitis to be HIV infected, as was the case in this study (20% and 17% of HIV seropositive cases who were case definition negative, respectively).