Fetal surgery using fetoscopic endoluminal tracheal occlusion for severe congenital diaphragmatic hernia: a single-center experience

PURPOSE

To provide a comprehensive report of the experience gained in the prenatal treatment of congenital diaphragmatic hernia (CDH) using fetoscopic endoluminal tracheal occlusion (FETO) following its implementation at a newly established specialized fetal medicine center.

METHODS

Mothers of fetuses with severe CDH were offered prenatal treatment by FETO.

RESULTS

Between 2018 and 2021, 16 cases of severe CDH underwent FETO. The median gestational age (GA) at balloon insertion was 28.4 weeks (IQR 27.8-28.6). The median GA at delivery was 37 weeks (IQR 34.4-37.8). The survival rate was 8/16 cases (50%). None of the survivors required home oxygen therapy at 6 months of age. Comparison between the survivors and deceased showed that survivors had balloon insertion 1 week earlier (27.8 vs. 28.4 weeks, p = 0.007), a higher amniotic fluid level change between pre- to post-FETO (3.4 vs 1.3, p = 0.024), a higher O/E LHR change between pre- to post-FETO (50.8 vs. 37.5, p = 0.047), and a GA at delivery that was 2 weeks later (37.6 vs. 35.4 weeks, p = 0.032).

CONCLUSIONS

The survival rate at 6 months of age in cases of severe CDH treated with FETO in our center was 50%. Our new fetal medicine center matches the performance of other leading international centers.

First trimester biomarkers for prediction of gestational diabetes mellitus

PURPOSE

To develop a first trimester prediction model for gestational diabetes mellitus (GDM) using obesity, placental, and inflammatory biomarkers.

METHODS

We used a first trimester dataset of the ASPRE study to evaluate clinical and biochemical biomarkers. All biomarkers levels (except insulin) were transformed to gestational week-specific medians (MoMs), adjusted for maternal body mass index (BMI), maternal age, and parity. The MoM values of each biomarker in the GDM and normal groups were compared and used for the development of a prediction model assessed by area under the curve (AUC).

RESULTS

The study included 185 normal and 20 GDM cases. In the GDM group, compared to the normal group BMI and insulin (P = 0.003) were higher (both P < 0.003). The MoM values of uterine artery pulsatility index (UtA-PI) and soluble (s)CD163 were higher (both P < 0.01) while pregnancy associated plasma protein A (PAPP-A), placental protein 13 (PP13), and tumor-necrosis factor alpha (TNFα) were lower (all P < 0.005). There was no significant difference between the groups in placental growth factor, interleukin 6, leptin, peptide YY, or soluble mannose receptor (sMR/CD206). In screening for GDM in obese women the combination of high BMI, insulin, sCD163, and TNFα yielded an AUC of 0.95, with detection rate of 89% at 10% false positive rate (FPR). In non-obese women, the combination of sCD163, TNFα, PP13 and PAPP-A yielded an AUC of 0.94 with detection rate of 83% at 10% FPR.

CONCLUSION

A new model for first trimester prediction of the risk to develop GDM was developed that warrants further validation.

Biophysical Characteristics of Erythrocytes during Acute Myocardial Infarction and Venous Thrombosis

The osmotic fragility (OF), density distribution (DDC) and electrophoretic mobility (EPM) of red blood cells were examined in groups of patients suffering from acute myocardial infarction (MI), arteriosclerotic heart disease and precordial pains (ASHD), and deep-vein thrombosis. In patients with acute MI there is a reduction in electric mobility which returns to normal range within 3 weeks. The slow RBCs were in no case slower than the slowest cells of a normal curve representing the oldest portion of the red cell population. In a definite percentage of these patients there are also changes in the OF and the DDC indicating a narrower cell population. These changes are apparently consequent to the disappearance of the slowest cells from the circulation. Mobility tests were done in buffered saline and after three washings. The cell mobility of normal patients was slowed after ½ to 1 hour incubation with the plasma of patients suffering from fresh MI. These results agree with the existence of plasma factors affecting the electric charge of RBCs. The mobility of red blood cells of patients with acute MI underwent incubation with normal plasma returned to normal. The cells of patients with ASHD and precordial pains show also a reduction in average mobility although in a lesser degree. The possibility that this group of patients suffer from micro-infarct not detected by the usual clinical tests, has been considered. Patients with deep-venous thrombosis show similar changes in cell mobility as patients with acute MI. A possible relation between reduced RBC electric mobility and thromboembolism among MI patients was suggested.

A Method for Automatic Recording of the Osmotic Fragility of Blood Platelets

A method for automatically recording the osmotic fragility of blood platelets, using a Fragiligraph, was developed. Platelet specimens taken from 20 healthy males and 9 females were examined. The mean rate of platelet change and the extent of increase in light transmission (LT) of washed platelets suspended in veronal, Tris, or phosphate buffered saline and dialyzed against water and 0.1% sodium chloride solutions, were analyzed. The recorded curves showed a slow phase lasting 2–74 sec, followed by a phase representing a rapid rate of platelet change in which gradually swelling of the platelets occurred concomitantly with an increase in the LT. This was followed by a third phase of plateau formation. The mean rate of platelet swelling was temperature-dependent, having twice the value at 37° C as at 15° C; the extent (% increase in LT) did not vary with temperature.

Nonvisualization of the Fetal Gallbladder: Can Levels of γ-Glutamyl Transpeptidase in Amniotic Fluid Predict Fetal Prognosisγ

Objective: In cases of nonvisualization of the fetal gallbladder (NVFGB), we investigated whether amniotic fluid levels of γ-glutamyl transpeptidase (GGTP) can distinguish normal development or benign gallbladder agenesis from severe anomaly such as biliary atresia. Methods: This is a retrospective cohort study of pregnancies in which the gallbladder was not visualized in the second-trimester fetal anatomy scan. Levels of GGTP in amniotic fluid were analyzed prior to 22 weeks of gestation by amniocentesis. Data were collected regarding other fetal malformations, fetal karyotype, and screening results for cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. Results: Of 32 cases of NVFGB, 27 (84%) had normal GGTP levels and a normal CFTR gene screening, and 1 of them had an abnormal karyotype. Three of the 5 cases with low GGTP were diagnosed with extrahepatic biliary atresia, proven by histopathological examination following termination of pregnancy. The fourth case had hepatic vasculature abnormality and the fifth isolated gallbladder agenesis. In 22 of 32 cases (68.7%), the gallbladder was detected either later in pregnancy or after delivery. Conclusion: The findings support low levels of GGTP in amniotic fluid, combined with NVFGB, as a sign of severe disease, mainly biliary atresia. Normal GGTP levels, concomitant with isolated NVFGB, carry a good prognosis.

Reference values for fetal penile length and width from 22 to 36 gestational weeks

OBJECTIVE

Current reference range values for fetal penile growth are based on length measurements. However, methodologies for measuring penile length differ among studies and from the standard technique used in children. We propose that the measurement of penile width may aid in its evaluation. The aim of the study was to create normograms for penile length and width.

METHODS

A prospective cross-sectional design was used. One hundred male fetuses at 22 to 36 gestational weeks were included. On ultrasound examination, penile length was measured from tip to base, where the penis joins the scrotum. Penile width was measured at the widest point across the penis. Reference values for the 5th and 95th percentiles were calculated for each gestational week.

RESULTS

There was a good correlation between gestational age and penile length (R(2) = 0.606) and width (R(2) = 0.683). The percentile of fetal weight estimation independently affected penile length and width. The interobserver correlation coefficient was 0.939 for length and 0.909 for width.

CONCLUSION

Reference range values of fetal penile length and width are presented for 22 to 36 weeks of gestation. These values correlate to gestational age and estimated fetal weight percentile. These reference range measurements may help the evaluation of suspected micropenis.

Sonographic estimation of fetal head circumference: how accurate are we?

OBJECTIVES

To assess the accuracy of sonographic estimation of fetal head circumference (HC).

METHODS

We compared sonographic estimations of fetal HC with actual measurements performed immediately after delivery using 3008 sonographic examinations performed within 3 days prior to delivery. The following measures of accuracy were calculated: correlation with actual HC, systematic error, random error, simple error, mean absolute percentage error and fraction of estimates within 5% of actual HC. Multivariate logistic regression analysis was used to identify factors affecting the accuracy of sonographic HC estimation.

RESULTS

There was a high correlation between sonographic and postnatal measurements of HC (r = 0.845, P < 0.001). Overall, sonographic HC measurements consistently underestimated actual HC measured postnatally (mean simple error, - 13.6 mm; 95% CI, - 13.2 to - 13.9), and the difference increased with gestational age. A high cephalic index (> 0.81) (odds ratio (OR), 0.3; 95% CI, 0.2-0.4), HC > 90(th) centile (OR, 0.5; 95% CI, 0.3-0.6), delivery by vacuum extraction (OR, 0.6; 95% CI, 0.4-0.8), gestational week (OR, 0.7; 95% CI, 0.6-0.9) and male fetal gender (OR, 0.8; 95% CI, 0.6-0.9) were associated with decreased sonographic accuracy. At term, breech presentation at the time of sonographic examination was associated with a higher sonographic accuracy compared with vertex presentation (-12.0; 95% CI, - 10.5 to - 13.5 vs. - 13.9 mm; 95% CI, - 13.6 to - 14.3; P = 0.02). The random error was relatively constant, and was unaffected by any of the obstetric factors studied.

CONCLUSION

Sonographic estimation of HC is associated with significant underestimation compared with the actual postnatal HC. This measurement error may have important clinical implications and should be taken into account in the interpretation of sonographically measured HC.

Hard to heal pressure ulcers (stage III-IV): efficacy of injected activated macrophage suspension (AMS) as compared with standard of care (SOC) treatment controlled trial

The objective of this study was to compare local injections of AMS with SOC treatments for stage III and IV pressure ulcers in elderly patients. It was designed as historically prospective 2-arms non-parallel open controlled trial, and conducted in a department of geriatric medicine and rehabilitation of a university affiliated tertiary hospital. We studied 100 consecutive elderly patients with a total of 216 stage III or IV pressure ulcers, 66 patients were assigned to the AMS group and had their wounds injected, while 38 patients were assigned to the SOC group. Primary outcome was rate of complete wound closure. Time to complete wound closure and 1-year mortality served as secondary outcomes. Statistical analyses were performed at both patient and wound levels. Percentage of completely closed wounds (wound level and patient level) were significantly better (p<0.001/p<0.001, respectively) in all patients in favor of AMS, as well as in the subset of diabetic patients (p<0.001/p<0.001). Similarly, AMS proved significantly better for the subset of those with leg ulcers and with baseline wounds ≤15 cm(2), compared with SOC. There were no statistically significant differences with regard to time to complete closure or 1-year mortality rates in the two groups. It is concluded that there is a significant difference in favor of stage III and IV wound closure rates by AMS, as compared with SOC treatments.

Prostaglandin E2 induction of labor for isolated oligohydramnios in women with unfavorable cervix at term

OBJECTIVE

To evaluate the maternal and neonatal outcomes of pregnancies complicated with isolated oligohydramnios at term, managed by induction of labor.

METHODS

We conducted a retrospective case-control study. 138 women with uncomplicated oligohydramnios at term [amniotic fluid index (AFI) < or =5 cm] and a low Bishop score (< or =6) underwent induction of labor with prostaglandin E2. These women were compared to 67 women who underwent induction of labor at 42 weeks' gestation and 276 women at low-risk pregnancy and spontaneous onset of labor, matched for parity and race.

RESULTS

Cesarean section (CS) rate was similar in the study and the post-date group (17.4 and 17.9%, respectively), but significantly higher than the spontaneous labor group (5.8%, OR 3.42, 95% CI 1.75-6.68). No differences were found with other outcomes.

CONCLUSION

Pregnancies with isolated oligohydramnios at term apparently are not at higher risk of perinatal complications, but induction of labor is associated with increased rate of CS.

Ex vivo activated human macrophages improve healing, remodeling, and function of the infarcted heart

BACKGROUND

Activated macrophages have a significant role in wound healing and damaged tissue repair. We sought to explore the ability of ex vivo activated macrophages to promote healing and repair of the infarcted myocardium.

METHODS AND RESULTS

Human activated macrophage suspension (AMS) was prepared from a whole blood unit obtained from young donors in a closed sterile system and was activated by a novel method of hypo-osmotic shock. The AMS (approximately 4 x 10(5) cells) included up to 43% CD14-positive cells and was injected into the ischemic myocardium of rats (n=8) immediately after coronary artery ligation. The control group (n=9) was treated with saline injection. The human cells existed in the infarcted heart 4 to 7 days after injection, as indicated by histology, human growth hormone-specific polymerase chain reaction, and magnetic resonance imaging (MRI) tracking of iron oxide-nanoparticle-labeled cells. After 5 weeks, scar vessel density (+/-SE) (25+/-4 versus 10+/-1 per mm2; P<0.05), myofibroblast accumulation, and recruitment of resident monocytes and macrophages were greater in AMS-treated hearts compared with controls. Serial echocardiography studies, before and 5 weeks after injection, showed that AMS improved scar thickening (0.15+/-0.01 versus 0.11+/-0.01 cm; P<0.05), reduced left ventricular (LV) diastolic dilatation (0.87+/-0.02 versus 0.99+/-0.04 cm; P<0.05), and improved LV fractional shortening (31+/-2 versus 20+/-4%; P<0.05), compared with controls.

CONCLUSIONS

Early after myocardial infarction, injection of AMS accelerates vascularization, tissue repair, and improves cardiac remodeling and function. Our work suggests a novel clinically relevant option to promote the repair of ischemic tissue.

Treatment of deep sternal wound infections post-open heart surgery by application of activated macrophage suspension

Postoperative sternal wound infection remains a significant complication and generally causes considerable morbidity and mortality. Macrophages play a major role in the process of wound healing. In order to evaluate the efficacy of local injection of activated macrophage suspensions into open infected sternal wound space, a retrospective case-control study was conducted. Sixty-six patients with deep sternal wound infection treated by activated macrophages (group 1) and 64 patients with deep sternal wound infection treated by sternal reconstruction surgery with various regional flaps (group 2), were matched for gender, age, and risk index. In up to 54 months of follow-up of group 1, 60 patients (91%) achieved complete wound closure. Two (3%) late deaths occurred unrelated to the procedure. Mortality rate in group 2 was 29.7% (19/64). Duration of hospitalization was 22.6 days in group 1 vs. 56.2 days in group 2. Patients with deep sternal wound infection following open heart surgery that were treated by activated macrophages had significantly less mortality as well as significant reduction of hospitalization in comparison to the surgically treated group. These results illustrate the advantages of using a biologically based activated macrophage treatment.

Macrophage suspensions prepared from a blood unit for treatment of refractory human ulcers

This paper presents an innovative method for the treatment of refractory wounds, starting with a blood unit, that is based on a biological approach. Local wound repair is one of the major unresolved clinical problems. Age, infection, clinical conditions such as diabetes mellitus, cardiac, renal, lung and liver failure, malnutrition and immunological deficiencies are among the reasons for wound repair delay or failure. Many chronic ulcers resist conventional treatment and do not heal for months and years, thus causing substantial morbidity and even mortality. The method for macrophage suspension treatment consists of introducing into the wound live cells that play a major role in the process of wound healing. The suspension is prepared from a blood unit of a healthy donor in a cost-effective, closed, sterile system. In the process of preparation, the macrophages are activated by hypo-osmotic shock to enhance their various functions in wound repair. The cells are applied to the wound either by local injection or by direct deposition into the wound. In most cases (90%), only one treatment is sufficient. Since 1995, macrophage suspensions have been used successfully in more than 1000 patients in several hospitals in Israel, without any side effects. Our results show that the use of a macrophage suspension is a safe and effective therapeutic strategy that shortens the healing period, reduces risk of complications and morbidity and improves the quality of life for long-suffering patients. This treatment requires no hospitalization and can be given on an ambulatory basis.

Activated macrophages for treating skin ulceration: gene expression in human monocytes after hypo-osmotic shock

Macrophages play a major role in almost all stages of the complex process of wound healing. It has been previously shown that the incorporation of a hypo-osmotic shock step, in the process of monocyte-concentrate preparation from a blood unit, induces monocyte/macrophage activation. As the macrophages are produced using a unique, closed and sterile system, they are suitable for local application on ulcers in elderly and paraplegic patients. Enhanced phagocytosis by the activated cells, as well as increased secretion of cytokines such as IL-1, IL-6, were detected in a recent study which are in accord with the very encouraging clinical results. In the present study, we used DNA microarrays to analyse the differential gene expressions of the hypo-osmotic shock-activated monocytes/macrophages and compare them to non-treated cells. Of the genes that exhibited differences of expression in the activated cell population, 94% (68/72) displayed increased activity. The mRNA levels of 43/68 of these genes (63%) were found to be 1.5-fold or higher (1.5-7.98) in the activated macrophages cell population as compared to the non-treated cells. Only four genes were found to have lower mRNA levels in the activated cells, with ratios of expression of 0.62-0.8, which may suggest that the changes are insignificant. A significant number of the genes that showed increased levels of expression is known to be directly involved in macrophage function and wound healing. This may correlate with the increased secretion of different cytokines by the activated macrophages depicted previously. Other groups of genes expressed are known to be involved in important pathways such as neuronal growth and function, developmental defects and cancer. The hypo-osmotic shock induces a gene expression profile of cytokines and receptors in the activated cells. These may evoke potential abilities to produce a variety of protein products needed in the wound healing process and may bring to light possibilities for other therapeutic applications of these cells.

Activation of human monocytes/macrophages by hypo-osmotic shock

Phagocytosis and secretion of interleukins and growth factors put the macrophage in the centre of the wound healing process. For the last four years over 400 human ulcers have been treated in elderly and paraplegic patients by local application of monocytes prepared from a blood unit, in a unique, closed, sterile system. The process of preparation includes a step of hypo-osmotic shock, which induces monocyte/macrophage activation. This is different from any other known method of activation. In the present study we evaluated the efficacy of the hypo-osmotic shock. We found enhanced levels of IL-1 (P = 0.004) and IL-6 (P = 0.001) in the incubation medium (100% autologous serum) of the activated cells, as compared with controls, prepared in the same system. The IL-1 reached a plateau after 6 and 12 h incubation at 37 degrees C, in both experimental and control incubation medium. The level of IL-6 was further elevated after 12 and 24 h incubation in experimental and control incubation mediums (P = 0.001). The phagocytosis of fluorescent beads was markedly enhanced after hypo-osmotic shock (P = 0.005). The osmotic shock induced macrophages were compared to those stimulated with LPS, and osmotic shock was proved to be at least as efficient method of stimulation as LPS.

Lack of known hepatitis virus in hepatitis-associated aplastic anemia and outcome after bone marrow transplantation

Viral infection has been shown to induce aplastic anemia, unidentified types of hepatitis being the most common cause for aplastic anemia-associated viral hepatitis. The survival rate for this group of patients after bone marrow transplantation with stem cells from an HLA-matched sibling is not well known. The aim of this study was to determine the prevalence of hepatitis G virus (HGV) and transfusion transmitted virus (TTV) infection in non-A, non-B, non-C hepatitis associated-aplastic anemia (HAAA) patients, and to define the role of bone marrow transplantation (BMT) as a therapeutic modality for this disease. Sixty-eight patients (43 males and 25 females) with aplastic anemia, underwent allogeneic BMT at the Hadassah University Hospital between 1981 and 1997. Onset of hepatitis was defined as jaundice and elevated alanine aminotransaminase (ALT) levels. Onset of aplastic anemia was defined as the first date on which varying degrees of pancytopenia occurred: hemoglobin level below 10 g/dl, WBC below 2 x 10(9)/l and low platelet count 10 x 10(10)/l. Serial serum samples from HAAA patients were assayed for virological and/or serological markers of hepatitis A, B, C, D, E, G viruses, TTV and parvovirus B19. Seventeen of the 68 patients with aplastic anemia (25%) suffered from hepatitis, 12 males and five females, ages 5 to 36 years. The mean interval between onset of hepatitis and first indication of aplastic anemia was 62 days (range 14-225 days). The development of aplastic anemia was unrelated to age, sex or severity of hepatitis. Ten of the 17 patients (59%) achieved complete ALT recovery prior to the diagnosis of aplastic anemia. Serum samples were available for 15 patients; none had evidence of acute or active hepatitis A, B, C, D, E, G and TTV virus infection at the time of diagnosis. Parvovirus B19 DNA sequences were not detectable in 10 of 12 tested cases; two positive results were detected in serum samples obtained after blood transfusion, making the analysis of these positive results difficult. All 17 patients underwent BMT. The mean post-BMT follow-up period was 38 months (range 1 day-123 months), five patients (30%) died 1 to 160 days post BMT, and 12 (70%) are alive 31 to 123 months after BMT. Relapsing hepatitis was not observed in any of the patients. In conclusion, HAAA is a disease of the young and the etiologic agent associated with HAAA remains unknown. HGV, TTV and parvovirus B19 sequences were not detected in any of the HAAA cases. The survival rate after BMT with stem cells from an HLA-matched sibling is similar to that for patients with non-hepatitis-associated aplastic anemia.

Maze learning impairment is associated with stress hemopoiesis induced by chronic treatment of aged rats with human recombinant erythropoietin

Mean cell volume (MCV) of erythrocytes has been reported to increase with age in humans, and to be negatively correlated with memory performance in humans and rats. We evaluated hematological changes in 21-mo old male Fischer 344 rats undergoing a 3-mo twice weekly subcutaneous injection of human recombinant erythropoietin (EPO). A baseline hematocrit (HCT) was obtained initially and repeated at monthly intervals to determine the effectiveness of EPO treatment. At 24-mo of age and after 3 mo EPO treatment, the rats were tested for their ability to learn a 14-unit T maze. Following maze testing, blood was drawn for hematologic analyses, including HCT, MCV, maximum swollen cell volume (MCVS), mean cell transit time (MCTT), and the membrane shear modulus of elasticity (G), the latter a derived measure of the relative elasticity of the red cell membrane. After 1 mo EPO treatment, HCT significantly increased compared to saline-injected controls. After 2 mo treatment, HCT began to decline but remained elevated above baseline levels even after 3 mo treatment. After 3 mo EPO treatment, MCV was significantly lower in EPO-treated rats compared to controls. These changes imply altered hemopoiesis to produce cells which undergo shrinkage associated with accelerated cellular aging. The lower MCV would have predicted a shorter MCTT which instead was unchanged. This observation suggested the presence of an additional factor contributing to the MCTT. The G, which measures the membrane contribution to deformability, very significantly increased with EPO treatment. This finding indicates an increased contribution of membrane properties to the MCTT after EPO treatment, which cancels the expected decrease in MCTT for smaller cells. After 3 mo of EPO treatment, aged rats exhibited significantly impaired maze learning compared to controls. A relationship between, changes in erythrocyte membrane properties and impaired function was indicated by a significant correlation (r=0.67, p <0.04) between G and errors in the 14-unit T-maze. These findings suggest that stress-induced erythropoiesis produces accelerated aging in the red blood cell population that may have functional implications (i.e., impaired learning ability).

Macrophage treatment of pressure sores in paraplegia

This report describes two cases where wound healing was achieved by local injection of a macrophage suspension after conventional treatments had failed for many years

Treatment of human ulcers by application of macrophages prepared from a blood unit

Decubital ulcers contribute to morbidity and mortality in elderly patients. Macrophages play a major role in the process of wound healing. We compared the efficacy of local treatment of decubital ulcers in elderly patients using macrophages prepared from a blood unit, vs. conventional treatments. Patients with decubital ulcers (n = 199) hospitalized during one year in a Geriatric Hospital in Israel, were included in the study. The ulcers of 72 patients (average age 82), who provided informed consent, by themselves or by family, were treated by local injection of macrophages prepared from a blood unit in a closed sterile system. The remaining 127 patients (average age 79) were treated conventionally and served as controls. No exclusion criteria were applied. Only a completely healed ulcer was considered a positive outcome of treatment. In the macrophage-treated group 27% (36 out of 131 ulcers) were healed compared to 6% (15 out of 248) in the control group (p < 0.001). There was also a significantly faster healing in the experimental group (p < 0.02). No side effects were noted. We conclude that Macrophages prepared from a blood unit, in cost-effective, closed, sterile system, are significantly more effective than conventional methods for the treatment of ulcers in elderly patients.

Chronic treatment with human recombinant erythropoietin increases hematocrit and improves water maze performance in mice

Erythropoietin is a glycoprotein produced endogenously in the kidney, which stimulates red blood cell production. We evaluated the effects of chronic treatment with recombinant human erythropoietin (epoetin alfa: EPO) on the performance of 6-month-old male C57BL/6J mice in a spatial learning task, the Morris water maze. Mice were treated with either EPO (1.5 U injected SC every other day) or vehicle (PBS also injected SC every other day). Results indicated that the treatment had no effect on maze performance after 8 weeks, but after 19 weeks the EPO-treated mice showed better performance compared to controls as measured by mean distance (centimeters) to reach the goal platform. The improved performance in EPO-treated mice at 19 weeks was accompanied by an increased hematocrit. After 32 wk of EPO-treatment, the hematocrit returned to baseline levels even though the size and density of the red blood cells were increased.

Relationship of hematological variables to learning performance in aged Fischer-344 rats

The relationship between hematological variables and the ability to perform behaviorally in two learning tests was evaluated in male F344 rats aged 22-24 months. Rats were screened for ability to meet criterion for learning one-way active avoidance in a straight runway task. Rats failing to meet criterion were given no further testing and were assigned to Group 1 (G1). Rats meeting criterion were tested in a 14-unit T-maze (2 days, 10 trials/day). Failure to negotiate the T-maze within 600 s on any three trials resulted in assignment to Group 2 (G2) with no further testing. Rats successfully completing both tasks constituted Group 3 (G3). Trunk blood was collected following behavioral testing and was assayed to determine red blood cell count (RBC), hematocrit (HCT), hemoglobin (HGB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), white blood cell count (WBC), bands (BND), polymorphs (POLY), lymphocytes (LYM), monocytes (MON), and eosinophils (EOS). The combined G1/G2 group had significantly lower RBC, HCT, HGB, and EOS but significantly higher MCV and MCH than G3 rats. Correlation analysis revealed a positive relationship of group membership (i.e., learning test completion) to RBC, HCT, HGB, and EOS, but a negative correlation of group membership to MCH. No significant correlation emerged between any hematological characteristic and performance in either behavioral task. These results suggest that a simple blood test to determine HCT may be a useful screen for removal of moribund rats from aging studies attempting to control for effects of health on behavioral performance in rodent models.

Life span of erythrocytes in late pregnancy

OBJECTIVE

Based on previous studies that demonstrated lighter and larger erythrocytes in late pregnancy, we hypothesized that the life span of erythrocytes in late pregnancy is shorter than in nonpregnant women.

METHODS

We used the density distribution of cells to evaluate the age distribution of erythrocytes in pregnant versus nonpregnant women and rats. The life span of erythrocytes was compared between pregnant rats and nonpregnant syngeneic rats of the same age using 51Cr for labeling erythrocytes.

RESULTS

Based on the density distribution of cells, a similar shift to lighter erythrocytes was found comparing pregnant to nonpregnant women and rats. The pregnant rat erythrocytes had a shorter life span by 9.2% (33.6 versus 36.9 days; P = .0010).

CONCLUSIONS

The life span of erythrocytes in pregnant rats is shorter than in nonpregnant ones. A similar shift in the age distribution of pregnant rat and pregnant human erythrocytes is probably associated with a similar life span of pregnant rat and pregnant human erythrocytes. The shorter life span of erythrocytes in late pregnancy may be attributed to higher erythropoietin levels in pregnancy, which induce "emergency hematopoiesis" resulting in younger reticulocytes and macrocytic erythrocytes, which are known to have a shorter life span.

Memory performance of young and old subjects related to their erythrocyte characteristics

Several papers reported in recent years on a change in the age population distribution of the circulating erythrocytes in old mice, rats, rabbits, and humans. The results indicate the presence of a chronologically younger cell population in old animals and humans. The cells are typically lower in density and larger. In some reports, the cells have higher levels of enzymatic activity. We wanted to know whether changes in the characteristics of the circulating erythrocytes in old people are related to the changes in cognitive performance often observed in the elderly. Twenty young (20-40) and 21 old (70-90) volunteers submitted to memory and blood tests. Density and size distribution, aspartate aminotransferase/glutamic oxalacetic transaminase (AST/GOT) activity, and the level of glycosylated hemoglobin (HbA1) of erythrocytes were determined. The Wechsler Memory Scale--Revised (Wechsler, 1987) was used to determine general memory and delayed recall scores for each subject. We have confirmed that old subjects have larger and less dense cells. Erythrocyte volume was the only blood parameter examined that revealed statistically significant correlations with memory performance. The old subjects with no age-related memory impairment had significantly smaller cells than the other old subjects.

The effect of selective desalivation on wound healing in mice

The effectiveness of wound licking in the acceleration of wound healing was evaluated in selectively desalivated mice. Rate of healing of experimentally induced cutaneous wounds was evaluated macroscopically by photography at 0, 2, 4, and 6 days after wounding. Sialadenectomy of submandibular and sublingual glands significantly slowed down wound healing in animals caged together compared to sham-operated controls. Separate caging as compared to caging in groups slowed down healing in sham-operated animals at day 2 but not at day 4 and 6. No effect on the rate of healing in sialadenectomized mice was observed in separate caging compared to mice caged in groups. Ligation of the parotid duct had an insignificant effect. The rate of wound healing of sublingual sialadenectomized mice was slower than that of sham-operated controls, but not as slow as those of sublingual and submandibular sialadenectomized mice. The results suggest that the rate of healing of experimentally induced cutaneous wounds of mice is slowed down when licking is prevented by separate caging which confirms previous reports. Licking with submandibular saliva seems to be more effective than sublingual saliva. Parotid saliva or minor salivary glands secretions are the least effective.

Age population distribution of erythrocytes in young and old healthy donors

Reports from several laboratories on a shorter life span of erythrocytes (E) in old animals and humans, induced the authors to search for a simple method for determining the younger age distribution of E in the blood of 20 old (over 70), as compared to 20 young (below 40), healthy donors. The following tests were performed: 1) Density Distribution of Cells (DDC), 2) Osmotic Fragility, 3) Agglutinability of E by Poly-L-lysine, 4) Analysis of Aspartate Amino Transferase (AST) activity, 5) Test for the presence of immunoglobulin on the surface of E (rosette formation on K562 cells); and 6) All the usual clinical and hematological tests were performed in order to avoid pathology. The most significant difference between the blood of the young and the old was found in the DDC. The shift of the cumulative curve indicated a younger population of cells in the blood of the elderly. The activity of AST was higher in the blood of the elderly, also indicating a younger cell population. The rosette formation was higher with the E from the blood of the elderly, indicating that the E, had more immunoglobulins on their surface than the E from the blood of the younger donors.

Promotion of wound repair in old mice by local injection of macrophages

Application of peritoneal macrophages to experimentally induced cutaneous wounds of old mice accelerates healing to levels almost comparable to those of untreated young animals. Slightly greater acceleration is observed when macrophages are obtained from young as opposed to old donors. These findings are consistent with a defect in macrophage function as a cause of impaired wound healing in senescence and suggest a possible therapeutic strategy.

Wound repair in mice as influenced by age and antimacrophage serum

The closure of bilateral, full-thickness cutaneous wounds made over the back with a sharp paper punch was measured with calipers and assessed histologically in C57BL/6J male mice for 10 days after wounding. Young (6 months) mice exhibited a significantly more rapid rate of wound closure and repair than did mature (15 months) or aged (26 or 27 months) mice. The repair rate in mature and aged mice did not differ. Young mice, injected subcutaneously at the wound sites with rabbit antimouse macrophage serum (RAMMS) 5 min before wounding and on days 1 and 3 after wounding, exhibited slow delayed closure of cutaneous wounds during days 1 to 4 after wounding, similar to that of untreated aged mice. The early closure rate of mice injected with normal rabbit serum or physiological saline was rapid, resembling that of untreated young mice. The results suggest that cutaneous wound repair in mice is another physiological phenomenon whose rate of change is age related, but not necessarily progressive to senescence. The results also imply that macrophage functional decline may contribute to the slowing of wound repair in middle-aged and aged mice compared to young mice.

The natural anti-alpha-galactosyl IgG on human normal senescent red blood cells

A highly sensitive antiglobulin test based on rosette formation due to the interaction between IgG bearing red blood cells (RBC) and Fc receptors on K562 cells, was used to study the immunoglobulin molecules present on human senescent RBC. Normal human RBC were separated into young and senescent subpopulations on the basis of age-dependent differences in density by centrifugation on a discontinuous density Percoll gradient, and by flotation on phthalate ester mixtures. The senescent but not the young RBC were found to bear membrane bound IgG. Most of the bound IgG molecules could be specifically eluted by galactose in its alpha-anomeric form. Antigalactosyl (anti-Gal) IgG antibodies with similar reactivity were found to be present in high titres in every one of the 400 normal human sera tested. The natural anti-Gal antibodies isolated from normal sera by affinity chromatography could bind to IgG depleted senescent RBC but not to young RBC. Erythrophagocytosis experiments indicated that the anti-Gal bound to the senescent RBC induced their destruction by macrophages. It is suggested that the natural anti-Gal antibodies interact with cryptic alpha-galactosyl residues which are exposed in the course of the RBC senescence and mediate the removal of these RBC from circulation by cells of the reticuloendothelial system.

The relationship between sialic acid content and peanut agglutinin binding on senescent and enzyme treated human erythrocytes

Young, old and neuraminidase treated human red blood cells (RBC) were investigated with peanut agglutinin (PNA), a lectin with a specificity similar to that of serum T-agglutinin. The effect of serum agglutinins on this interaction was also investigated. The density and distribution of PNA receptors were evaluated by agglutination with PNA and binding of ferritin-conjugated PNA (PNA-F), or PNA labeled with radioactive iodine [( 131I] PNA). The results were correlated with the distribution of membrane bound sialic acids, as evaluated by chemical analysis and rate of agglutination with poly-L-lysine (PLL). Untreated RBC of all ages did not agglutinate with PNA and failed to bind PNA-F and [131I] PNA. Treatment of young RBC with neuraminidase, which resulted in reduction of membrane-bound sialic acids to an extent similar to that of physiologically aged RBC, resulted in the concomitant exposure of PNA binding sites and in the agglutination of these cells by autologous serum. Pretreatment of the neuraminidase treated RBC with autologous serum resulted in partial inhibition of the binding capacity of PNA on the RBC. The results indicate that the normal age-related loss of sialic acids in circulating RBC is not identical with enzymatic removal of sialic acids by neuraminidase. The observations suggest that different mechanisms are functional in the recognition and sequestration of old RBC and of RBC treated with neuraminidase.

Changes of cell shape and surface charge topography in ATP-depleted human red blood cells

ATP depletion crenates human red blood cells. With ferritin-avidin (FA) and cationized ferritin (CF) cell surface labeling, it is demonstrated that the discocyte----crenated shape transformation alters the two-dimensional topography of negative charge sites. With restoration of ATP levels, cell shape and charge topography return to normal. Concurrent changes in red cell shape and surface charge topography can be explained by associations between membrane integral proteins and the red cell cytoskeleton.

Surface charge and flow properties of endothelial membranes in aging rats

The morphological features, surface charge and fluid properties of the membranes of aortic endothelial cells of young and old Wistar rats were studied by electron microscopy. Remarkable structural changes in the endothelial cells and subendothelial layer were observed in the aorta of old rats, due to accumulation of fibrillar and granular substances and cellular debris. Analysis of the possible age-related alterations in the permeability properties of the aortic endothelium indicated that positively charged macromolecules such as cationized ferritin are more rapidly transported through the endothelium of old rat aorta, as compared to young rats, thereby leading to their accumulation in the aortic intima of the old animal. Cytochemical analyses of the charge properties of endothelial cell membranes revealed that despite the general similarity in the anionic site density and distribution, endothelial cells from old rat aorta are characterized by a significant decrease in the density of cell-surface sialic acids. The ability of anionic sites in the luminal front of the endothelial cells to redistribute reversibly by lateral migration under the influence of multivalent ligands was shown to be an important factor in the mechanism of internalization and transport of cationized ferritin through the endothelial barrier. It was therefore suggested that the local changes in the surface charge properties due to an interaction with positively charged substances, may account for the accumulation of plasma components in the blood vessel intima of the old animals.

Phagocytosis of nucleated and mature beta thalassaemic red blood cells by mouse macrophages in vitro

Physiological or experimental decrease in sialic acid (SA) content on the red blood cell (RBC) membrane is believed to play an important role in the recognition of these cells by macrophages. Since there is a 20-30% decrease in the SA content on the membrane of thalassaemic RBC, the interaction between macrophages and these RBC was studied in vitro. Using mouse peritoneal macrophages, it was found that these macrophages 'recognize' and phagocytize thalassaemic RBC while RBC from normal donors are hardly phagocytized. The average level of phagocytosis of thalassaemic RBC from splenectomized patients was found to be 22-fold higher than that of RBC from normal donors. The phagocytized cells consisted of both mature and nucleated RBC. Mouse peritoneal macrophages seem to be a useful in vitro system for the study of the accelerated sequestration and shortened life span of thalassaemic RBC.

Surface charge characteristics of cells from malignant cell lines and normal cell lines of the human hematopoietic system

Cells from malignant and normal lines of human hematopoietic origin were studied for their surface charge characteristics with the use of the following criteria: 1) the electron microscopic appearance of cell membranes after labeling with cationized ferritin (CF) either before or after glutaraldehyde fixation, 2) electrophoretic mobility, 3) total sialic acid content, and 4) agglutinability with poly-L-lysine (PLL). CF induced a time-dependent redistribution of surface receptors in unfixed malignant cells but not in unfixed normal cells. After 10 seconds of labeling with CF, both normal and malignant unfixed cells showed a uniform and even labeling pattern. After 5 minutes of labeling, malignant cells exhibited a highly pronounced pattern of clusters and patches, as distinct from a random and even pattern exhibited by normal cells. Both normal and malignant cells after fixation exhibited an equivalent random and even labeling pattern with CF, independent of the duration of labeling. The malignant cells studied possessed less sialic acid, had a lower electric mobility, and were agglutinated more readily with PLL than were the normal cells.

Age-related changes in aortic intima of rats

The aortic intima of young and old Wistar rats was studied by light and electron microscopy. The endothelial cells of young rats are flat and regular and lie adjacent to the internal elastic lamina (IEL). Endothelial cells of old rats have irregular shapes and sizes and bulge into the lumen. Long protrusions connect these cells to the IEL through a layer of granular and fibrillar material that separates the IEL from the endothelium. This material is PAS and Alcian blue positive and increases with age. There are twice as many pinocytic vesicles on the luminal front of endothelial cells of old rats as compared to the tissue front. Endothelial cells of young rats have similar numbers of vesicles on the two fronts. No significant difference was found between the charge density of the luninal plasmalemma of young and old rats; however, significantly less sialyl groups were found on endothelial cells of old rats. A marked difference in the labeling pattern of the IEL by cationized ferritin (CF) was observed between young and old rats.