Bioactivities of alternative protein sources and their potential health benefits.

Increasing the utilisation of plant proteins is needed to support the production of protein-rich foods that could replace animal proteins in the human diet so as to reduce the strain that intensive animal husbandry poses to the environment. Lupins, quinoa and hempseed are significant sources of energy, high quality proteins, fibre, vitamins and minerals. In addition, they contain compounds such as polyphenols and bioactive peptides that can increase the nutritional value of these plants. From the nutritional standpoint, the right combination of plant proteins can supply sufficient amounts of essential amino acids for human requirements. This review aims at providing an overview of the current knowledge of the nutritional properties, beneficial and non-nutritive compounds, storage proteins, and potential health benefits of lupins, quinoa and hempseed.

Localization of oestrogen receptors alpha and beta in human testis.

Cellular localization of oestrogen receptor alpha (ERalpha) and beta (ERbeta) proteins were studied in human testis samples using immunohistochemistry, and the expression of the corresponding mRNA was examined with reverse transcription-polymerase chain reaction (RT-PCR). Seven men, aged 28-48 years, who underwent diagnostic testicular biopsy because of azoospermia or to give spermatozoa for intracytoplasmic injection for infertility treatment, donated tissue for the study. One of them had anejaculation but normally functioning testes, and one was diagnosed as having Sertoli cell-only syndrome (SCOS). In addition, expression of ERbeta protein was examined in one testis sample obtained from a man undergoing a sex change operation. Strong ERbeta immunoreactivity was detected in the nuclei of spermatogonia, spermatocytes and early developing spermatids. Elongating spermatids, mature spermatozoa, Sertoli and Leydig cells were all negative for ERbeta. The presence of ERbeta protein was confirmed in Western analysis. With RT-PCR, both wild-type ERbeta and ERbetacx, the isoform which represses wild-type ER function, were easily detected. In most cases, ERbetacx mRNA was more abundantly expressed than wild-type ERbeta. The patient with SCOS expressed neither ERbeta isoform. Neither ERalpha protein nor ERalpha mRNA was detected in any of the samples. We conclude that in the human testis, ERbeta is likely to be the ER that mediates the effects of oestrogen.

Estrogen receptor (ER) beta, a modulator of ERalpha in the uterus.

Many of the effects of estrogens on the uterus are mediated by ERalpha, the predominant ER in the mature organ. Because of the poor reproductive capacity of ERbeta knockout (BERKO) female mice (small litter size, multiple-resorbed fetuses), the role of uterine ERbeta was explored. In the immature uterus, ERalpha and ERbeta are expressed at comparable levels in the epithelium and stroma, and 17beta-estradiol (E(2)) treatment decreases ERbeta in the stroma. The immature uterus of untreated BERKO mice exhibits elevated levels of progesterone receptor (PR) and the proliferation-associated protein, Ki-67. It also exhibits exaggerated responsiveness to E(2), as indicated by enlargement of the lumen, increase in volume and protein content of uterine secretion, induction of the luminal epithelial secretory protein, complement C3, and its regulatory cytokine IL-1beta, and induction of vascular endothelial growth factor and insulin-like growth factor 1 but not its receptor. As expected, E(2) increased PR in the stroma and decreased it in the luminal epithelium of wild-type mice. In the BERKO uterus, E(2) induced PR in the stroma but did not down-regulate it in the epithelium. Increased cell proliferation and exaggerated response to E(2) in BERKO suggest that ERbeta plays a role in modulation of the effects of ERalpha and in addition (or as a consequence of this) has an antiproliferative function in the immature uterus.

Testicular biopty gun needle biopsy in collecting spermatozoa for intracytoplasmic injection, cryopreservation and histology.

Using testicular spermatozoa from either open biopsy (29 cycles) or biopty gun needle biopsy (49 cycles), a total of 81 intracytoplasmic sperm injection (ICSI) cycles among 57 couples were carried out from January, 1994 to September, 1997. In six cycles, no spermatozoa were obtained, and in three cycles spermatozoa from both needle and open biopsies were used. The fertilization (37% after open and 41% after needle biopsy) and pregnancy rates (29% per embryo transfer compared with 16% per embryo transfer) were similar after both open and needle biopsies. Five pregnancies were achieved among the 14 couples with non-obstructive azoospermia of the male partner, four of these after needle biopsy. It was possible to use cryopreserved testicular spermatozoa after both needle and open biopsies, and one pregnancy started after using cryopreserved testicular spermatozoa in both groups. Histological needle biopsy was carried out in 62 cases, and they were all diagnostic, giving 15-20 cross-sections of seminiferous tubuli per biopsy. Testicular needle biopsy using a 14 gauge biopsy needle gave a sufficient amount of tissue and spermatozoa for ICSI, cryopreservation and histology, even in non-obstructive azoospermia. This technique is simpler and cheaper than open biopsy and, hence, it can be regarded as the optimal method for the retrieval of testicular spermatozoa.

Do recorded doses overestimate true doses received by Chernobyl cleanup workers? Results of cytogenetic analyses of Estonian workers by fluorescence in situ hybridization.

Studies of workers who were sent to Chernobyl after the 1986 reactor accident are being conducted to provide a better understanding of the effects of chronic low-dose radiation exposures. A crucial component to these investigations is an accurate assessment of the radiation doses received during the cleanup activities. To provide information on biological measurements of dose, fluorescence in situ hybridization (FISH) with whole-chromosome painting probes has been applied to quantify stable chromosome aberrations (translocations and insertions) among a defined cohort of 4,833 cleanup workers from Estonia. Cytogenetic analysis of 48-h lymphocyte cultures from 118 Estonian cleanup workers (10.3 cGy mean recorded dose; 25 cGy maximum), 29 Estonian population controls and 21 American controls was conducted by three laboratories. More than 258,000 painted metaphases were evaluated. Overall, we observed lower translocation frequencies than has been reported in previous studies using FISH among Chernobyl cleanup workers. In our data, a clear association with increased levels of translocations was seen with increasing age at blood drawing. There was no correlation, however, between aberration frequency and recorded measurements of physical dose or any category of potential high-dose and high-dose-rate exposure such as being sent to Chernobyl in 1986, working on the roof near the damaged nuclear reactor, working in special zones or having multiple tours. In fact, the translocation frequency was lower among the exposed workers than the controls, though not significantly so. To estimate the level of effect that would have been expected in a population of men having an average dose of approximately 10 cGy, blood from six donors was exposed to low-LET radiation, and more than 32,000 metaphases were scored to estimate dose-response coefficients for radiation-induced translocations in chromosome pairs 1, 2 and 4. Based on these results, we estimate that had this group of 118 men received an average whole-body dose of 10-11 cGy, as chronic or acute exposures, an increase in the mean frequency of chromosome translocations of more than 40-65% would have been observed in their lymphocytes compared to findings in nonirradiated controls. In spite of evaluating more than a quarter of a million metaphases, we were unable to detect any increase in the mean, median or range in chromosome aberrations in lymphocyte cultures from a group of Estonian men who took part in the cleanup of the Chernobyl nuclear power site and those who did not. We conclude that it is likely that recorded doses for these cleanup workers overestimate their average bone marrow doses, perhaps substantially. These results are consistent with several negative studies of cancer incidence in Chernobyl cleanup workers and, if borne out, suggest that future studies may not be sufficiently powerful to detect increases in leukemia or cancer, much less distinguish differences between the effects of chronic compared to brief radiation exposures.

Thyroid nodularity and cancer among Chernobyl cleanup workers from Estonia.

Thyroid examinations, including palpation, ultrasound and, selectively, fine-needle aspiration biopsy, were conducted on nearly 2,000 Chernobyl cleanup workers from Estonia to evaluate the occurrence of thyroid cancer and nodular thyroid disease among men with protracted exposure to ionizing radiation. The examinations were conducted in four cities in Estonia during March-April 1995, 9 years after the reactor accident. The study population was selected from a predefined cohort of 4,833 cleanup workers from Estonia under surveillance for cancer incidence. These men had been sent to Chernobyl between 1986 and 1991 to entomb the damaged reactor, remove radioactive debris and perform related cleanup activities. A total of 2,997 men were invited for thyroid screening and 1,984 (66%) were examined. Estimates of radiation dose from external sources were obtained from military or other institutional records, and details about service dates and types of work performed while at Chernobyl were obtained from a self-administered questionnaire. Blood samples were collected for assay of chromosomal translocations in circulating lymphocytes and loss of expression of the glycophorin A (GPA) gene in erythrocytes. The primary outcome measure was the presence or absence of thyroid nodules as determined by the ultrasound examination. Of the screened workers, 1,247 (63%) were sent to Chernobyl in 1986, including 603 (30%) sent in April or May, soon after the accident. Workers served at Chernobyl for an average of 3 months. The average age was 32 years at the time of arrival at Chernobyl and 40 years at the time of thyroid examination. The mean documented radiation dose from external sources was 10.8 cGy. Biological indicators of exposure showed low correlations with documented dose, but did not indicate that the mean dose for the population was higher than the average documented dose. Ultrasound examinations revealed thyroid nodules in 201 individuals (10.2%). The prevalence of nodules increased with age at examination, but no significant associations were observed with recorded dose, date of first duty at Chernobyl, duration of service at Chernobyl, building the sarcophagus or working on the roof of neighboring buildings or close to the damaged reactor. Nodularity showed a nonsignificant (p(1) = 0.10) positive association with the proportion of lymphocytes with chromosome translocations, but associations with the frequency of variant erythrocytes in the GPA assay were weak and unstable (p(1) > or = 0.46). The majority of fine-needle biopsies taken on 77 study participants indicated benign nodular disease. However, two cases of papillary carcinoma and three benign follicular neoplasms were identified and referred for treatment. Both men with thyroid cancer had been sent to Chernobyl in May of 1986, when the potential for exposure to radioactive iodines was greatest. Chernobyl cleanup workers from Estonia did not experience a markedly increased risk of nodular thyroid disease associated with exposure to external radiation. Possible reasons for the apparent absence of effect include low radiation doses, the protracted nature of the exposure, errors in dose measurement, low sensitivity of the adult thyroid gland or the insufficient passage of time for a radiation effect to be expressed.

Unstable and stable chromosomal aberrations in lymphocytes of people exposed to Chernobyl fallout in Bryansk, Russia.

Analyses of unstable and stable chromosomal aberrations in peripheral blood lymphocytes were used in the assessment of radiation exposure of residents of a village situated in the Chernobyl fallout-contamination zone of Bryansk, Russia. Blood samples were taken from subjects residing in villages with high (> 1100 kBq/m2 137 Cs; Mirnyi) and very low (< 37 kBq/m2 137 Cs; Krasnyi Rog) contamination, 7 years after the Chernobyl accident. The groups were matched by age, sex, smoking habits and previous medical radiological exposures. A total of 200 people (100 exposed, 100 controls) were analysed for the presence of unstable aberrations from Giemsa-stained slides. To study stable aberrations, chromosome painting analyses were performed on 100 subjects (50 exposed, 50 controls), using painting probes for chromosomes 1, 2 and 4 and a pancentromeric probe. People living in the contaminated area showed significantly higher rates of unstable chromosome-type aberrations but not chromatid-type aberrations in their lymphocytes, indicating radiation exposure as a causative factor for the observed difference. No significant differences were found in the aberration rates between the two areas by the chromosome painting method. The levels of chromosome exchanges were low in both populations, but consistently higher in Mirnyi compared with the control area. The magnitude of radiation exposure resulting from Chernobyl fallout was estimated on the basis of excess stable chromosomal aberrations in the lymphocytes of the Mirnyi population compared with the controls.

The effects of the dietary intakes of copper, iron, manganese, and zinc on the trace element content of human milk.

Fifteeen breast-feeding mothers who volunteered for a study of trace elements in human milk, kept two 7-day food records during the course of lactation. The 1st survey week ranged from 6 to 8 weeks and the 2nd survey week from 17 to 22 weeks postpartum. The milk samples submitted for analysis represented a sample of every feed during a period of 24 hr and contained foremilk and hindmilk in equal proportions. The 7-day food records were handled by a computing system to give an average daily food consumption and nutrient intake, but iron was the only trace element given by the system. In order to estimate the trace element intakes of the mothers, mixtures were prepared to represent the average daily food consumption. The trace element concentrations of the mixtures and milk samples were analyzed using the atomic absorption spectrophotometric method. The estimated average daily copper intake was 1.8 mg, the iron intake 16 mg, the manganese intake 5 mg, and the zinc intake 13 mg. The mean copper, iron, manganese, and zinc concentrations of the milk samples were 0.36 +/- 0.07 mg/liter, 0.40 +/- 0.10 mg/liter, 4.5 +/- 1.8 microgram/liter, and 1.89 +/- 0.74 mg/liter for the 1st survey week and 0.21 +/- 0.07 mg/liter, 0.29 +/- 0.09 mg/liter, 4.0 +/- 1.5 microgram/liter, and 0.72 +/- 0.44 mg/liter for the 2nd survey week. A significant positive correlation (P less than 0.01) was observed in the 2nd survey week between maternal manganese intake and the manganese content of human milk. The intake of copper, iron, and zinc, at the present level of intake, did not seem to affect the corresponding trace element levels in human milk.