ARIC hemostasis study--III. Quality control. Atherosclerosis Risk in Communities

Methods and results from the quality assurance program of the Atherosclerosis Risk in Communities (ARIC) Study regarding hemostasis variables are presented, following up previous reports in this journal on standardized procedures for blood collection and processing (7) and an organized plan for the performance of those procedures (8). Efforts were made to control for and assess all sources of variability, from venipuncture to laboratory analysis, including also local field center processing and sample shipping. The quality control program included (a) a standardized protocol for blood collection and processing; (b) training, certification, and annual recertification of field center personnel for blood collection and processing; (c) monitoring of fasting times, phlebotomy times, processing times, and shipping problems; (d) hemostatic laboratory internal quality control; (e) a replicate blood sample program; (f) an intraindividual variability study; and (g) continual monitoring of quality control and study participants' data. This paper focused on items (c), (d), and (e). Measures of variation, generally standard deviations and coefficients of variation, are estimated for replicate blood sampling and internal quality control data, for activated partial thromboplastin time, fibrinogen, factor VII and VIII activity, von Willebrand factor, antithrombin-III, and protein C. The results demonstrate that it is possible to reliably measure these hemostatic variables in a large multicenter study.

Tumor necrosis factor-alpha alters steroidogenesis and stimulates proliferation of human ovarian granulosal cells in vitro

OBJECTIVE

To determine if tumor necrosis factor alpha (TNF-alpha) altered human granulosa-luteal cell proliferation and steroidogenesis.

DESIGN

Aspirates of follicles from women undergoing in vitro fertilization were subjected to Percoll gradients to collect an enriched population of granulosa-luteal cells. The granulosa-luteal cells were subjected to culture for a period of 10 or 20 days in the presence or absence of various doses of human recombinant TNF-alpha (0.1 to 10.0 ng/mL).

PATIENTS

Granulosa-luteal cells from nine patients were evaluated for their response to TNF-alpha in vitro. Patients with three follicles > 16 mm and a serum estradiol (E2) concentration of > 1,836 pmol/L were selected for study.

RESULTS

Tumor necrosis factor-alpha increased granulosa-luteal cell number. By day 10 of culture, 10 ng TNF-alpha/mL doubled cell number and > 95% of the cells exhibited 3 beta-hydroxysteroid dehydrogenase. Tumor necrosis factor-alpha at 10 ng/mL increased progesterone (P) accumulation from day 4 through day 20 of culture. Tumor necrosis factor-alpha also increased E2 secretion but in a biphasic manner. During the first 14 days of culture, TNF-alpha increased E2, but thereafter E2 decreased to basal values by day 20. When steroidogenesis was expressed per 1,000 cells per days of culture, TNF-alpha did not increase P beyond controls but significantly increased E2 for the first 14 days of culture after which E2 per 1,000 cells declined.

CONCLUSIONS

The results indicate that TNF-alpha stimulates granulosal-luteal cell growth and E2 secretion in vitro, and thus TNF-alpha may promote cellular events associated with formation of the corpus luteum; i.e., granulosa-cell proliferation and steroidogenesis.

Evidence for lipopolysaccharide binding in human granulosa-luteal cells

We investigated whether human granulosa-luteal (GL) cells exhibited lipopolysaccharide (LPS)-binding protein, and the response of follicular aspirate cells to LPS in vitro. Follicular aspirates taken from a human in-vitro fertilization and gamete intra-fallopian-tube transfer programme were subjected to Percoll gradients in order to isolate an enriched population of GL cells. GL cells exhibited specific LPS-binding protein, detected by autoradiography of the cellular lysate on SDS-PAGE after the cells were specifically labelled with a radioiodinated, photoactivable and reducible LPS derivative. LPS binding to the cells was also detected by the appearance of immunofluorescence associated with the cellular membrane when incubated with a fluorescent conjugated LPS receptor antibody. Ninety-four per cent of the cells exhibiting immunofluorescent LPS-binding protein were also positive for the steroidogenic enzyme 3 beta-hydroxysteroid dehydrogenase, as detected by cytochemistry. In order to detect a response to LPS, the enriched population of GL cells were cultured in vitro in the presence or absence of LPS; after 16 h of culture, tumour necrosis factor-alpha (TNF) mRNA was detected by reverse transcription-polymerase chain reaction and Southern blot analysis of the amplified cDNA. The expression of TNF mRNA was enhanced when the cells were cultured in the presence of LPS, which also significantly enhanced TNF secretion into the media during the 16-h period. These results reveal that GL cells exhibit LPS-binding protein and thus increased TNF secretion occurs in response to LPS in follicular aspirate cells. The source of ovarian TNF may be leukocytes, macrophages and/or GL cells.

The rapid infusion system: a superior method for the resuscitation of hypovolemic trauma patients

The rapid infusion system (RIS), which can deliver fluids/blood products rapidly at precise rates and normothermic conditions, was compared with conventional fluid administration (CFA) in a randomized study of 36 hypovolemic trauma patients. Admission stratification criteria of the groups were similar relative to age, Glasgow Coma Score (GCS), Injury Severity Score (ISS) and plasma lactate. Despite the lack of difference in blood loss between the 24-h survivors of the two groups, the CFA group required greater total fluids (23.6/20.21), red blood cells (5.5/4.61), fresh frozen plasma (FFP) (2.8/1.91), platelets (523/204 ml), and crystalloids (12.9/10.61). Lactate levels were lower in the RIS group at virtually all times from hours 1 to 24 (4.3/5.3 mM/l, t-value = 3.3, DF = 279, P = 0.001). Post-admission hypothermia was greater in the CFA group at all times during the first 24 h (35.2/36.4 degrees C, t-value = 5.6, DF = 250, P = 0.001). The mean partial thromboplastin time was significantly higher in the CFA group (47.3/35.1 s, t-value = 3.1, DF = 279, P = 0.002). The PTT and PT were related to the degree of lactic acidosis (P = 0.0001) and hypothermia (P = 0.001) but not to the amount of FFP given (P = 0.14). The hospital costs, days in the ICU, and days on the ventilator were greater for the CFA group, as was the incidence of pneumonia (0/11 vs. 6/17; P = 0.03). Hypovolemic trauma patients resuscitated with the RIS needed fewer fluid/blood products and had less coagulopathy; more rapid resolution of hypoperfusion acidosis; better temperature preservation; and fewer hospital complications than those resuscitated with conventional methods of fluid/blood product administration.

Immunological evidence for a human ovarian tumor necrosis factor-alpha

Tumor necrosis factor-alpha (TNF alpha) was localized to follicular and luteal compartments of the human ovary using a biotin strept-avidin immunocytochemical technique with polyclonal antibodies to human recombinant TNF alpha. Immunoreactive TNF alpha (I-TNF) was observed in granulosa cells of healthy antral and atretic follicles and appeared to be secreted by the granulosa cells, since it was present in the follicular fluid surrounding antral and degenerating granulosa. Preantral follicles did not exhibit I-TNF. I-TNF was in the cytoplasm of large granulosa-lutein cells and small paraluteal cells. Granulosa cells cultured on an Immobilon membrane exhibited I-TNF in the cytoplasm and I-TNF released onto the membrane, which appeared as a dark-red stain after immunolocalization. Granulosa cells cultured on plastic slides exhibited I-TNF throughout the cytoplasm. To determine if I-TNF was secreted by granulosa cells, granulosa cell-conditioned medium was examined for the presence of TNF by a double sandwich enzyme-linked immunosorbant assay using both monoclonal and polyclonal antibodies to human recombinant TNF alpha. Conditioned medium contained up to 800 pg TNF/500,000 cells after 24 h of culture. I-TNF was also found (100-170 pg/mL) in human follicular fluid. Immunoblot assay of I-TNF in cultured granulosa revealed approximately 240 pg TNF/250,000 cells. The results indicate that the human ovary contains I-TNF, and thus, a paracrine and/or autocrine role of TNF in human ovarian follicular function seems likely.

Plasma gonadotropin-releasing hormone profiles after intravenous and subcutaneous bolus injection in thin and obese women

Other studies of plasma gonadotropin-releasing hormone profiles after bolus injection have revealed earlier, sharper peaks and higher blood gonadotropin-releasing hormone levels with the intravenous (IV) than with the subcutaneous route of administration. We used both routes to administer gonadotropin-releasing hormone by bolus injection to thin and obese subjects. Plasma gonadotropin-releasing hormone profiles after IV administration were similar in both groups. The subcutaneous route produced flatter, delayed, and lower peaks, an effect markedly exaggerated in obese subjects, who demonstrated 95% lower peak gonadotropin-releasing hormone levels compared with the IV route and 64% lower levels than thin subjects after subcutaneous administration. These findings may be relevant to therapeutic failures observed in obese subjects using the subcutaneous route.