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We report here one observed and two potential cases of infanticide during a brief period of 1 month after a dominant male replacement in one group of black capuchin monkeys in Iguazú National Park, Argentina. We also compile infant disappearances and demographic data in seven groups followed from 1–14 years. Behavioral and molecular data showed that the probability that an infanticidal male would kill his own progeny is very low in this species. Females that lost infants less than 6 months old had shorter interbirth intervals than females whose infants survived (14.12±5.32 months, n=17 vs. 20.42±5.65 months, n=34). Females whose infants die shortly after takeovers mate with the presumed infanticidal male during the most fertile days of their subsequent estrous periods giving this male a high probability of siring the new progeny. We recorded 181 proceptive periods and 52 births from 18 adult females in two groups. Most proceptive periods were concentrated during a conception season, but there was an increase in sexual behavior after male takeovers. Seven females copulated while pregnant after the observed male takeover, an unusual behavior in this species in years of group stability. Of 24 infants born during takeover years, 62.5% did not survive the first year, whereas only 22.5% of 80 infants died in years without male replacements. We found a significant positive association between infant mortality and male takeovers, but not with food provisioning. The main cause of infant mortality in this population is associated with male takeovers. Our results suggest that infanticide can have an important effect on the behavior of this species, selecting for female behaviors that function to reduce infanticide risk. Am. J. Primatol. 70:473–484, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Food abundance and distribution have played a central role in the conceptual theory of primate socioecology [Janson, Behaviour 105:53–76, 1988; Isbell, Behavioral Ecology 2:143–155, 1991; Sterck et al., Behavioral Ecology and Sociobiology 41:291–309, 1997; van Schaik, In: Standen V, Foley RA, editors, Comparative Socioecology. Oxford: Blackwell. p 195–218, 1989]. This theory predicts that agonistic (“contest”) competition should occur when food is distributed in discrete, defensible patches; in contrast, when food sources are distributed uniformly or randomly, non-agonistic (“scramble”) competition is expected. Primatologists usually measure resource density and patchiness from a botanical perspective, ignoring the biology of the animal being studied. Such an approach may be irrelevant in terms of how animals view the dispersion of resources. Using a novel focal-tree method that measures resource availability on a scale that is both spatially and temporally relevant to the animal under investigation, we take a cost-benefit approach to predict the frequency of food-related agonism in white-faced capuchin monkeys (Cebus capucinus) from 11 ecological and social variables. We retained four variables in the regression model: two representing the opportunity for aggression (i.e., feeding bout length and the number of feeding adult females), and two representing opportunity costs (i.e., fruit abundance and the number of potential feeding sites in the focal tree). The results of this study indicate that the amount of food-related aggression in white-faced capuchins can be predicted by variables representing the costs and benefits of contesting a food resource. Am. J. Primatol. 69:533–550, 2007. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The MRL-lpr/lpr mouse strain is a commonly used model of the human autoimmune disease systemic lupus erythematosus (SLE). Although much is known about the contribution of the lpr Fas mutation to B cell tolerance breakdown, the role of the genetic background of the MRL strain itself is less well explored. In this study, we use the MD4 anti-hen egg lysozyme Ig (IgHEL) transgenic system to explore B cell function in MRL+/+ and non-autoimmune mice. We demonstrate that MRL IgHEL B cells show spontaneous hyperactivity in the absence of self-antigen, which is associated with low total B cell numbers but an expansion of the marginal zone B cell population. However, B cell anergy is normal in the presence of soluble lysozyme [soluble hen egg lysozyme (sHEL)], and MRL IgHEL B cells undergo normal elimination in the presence of sHEL when competing with a polyclonal C57BL/6 B cell repertoire. We conclude that B cell hyperactivity may contribute to the autoimmune phenotype of MRL+/+ and MRL-lpr/lpr strains when it initiates antibody responses to rare or sequestered antigens that are below the threshold for tolerance induction, but that there is no B cell intrinsic defect in anergy in MRL mice. [ABSTRACT FROM AUTHOR]

In order to investigate the T-cell receptor (TCR) Vβ usage in different T-cell subsets, the authors performed flow cytometric analyses using a large panel of TCR Vβ-specific monoclonal antibodies on CD4+, CD8+ CD28+ and CD8+ CD28- T cells from 15 random blood donors, six umbilical cords and seven human leucocyte antigen (HLA) identical non-twin sibling pairs. The authors found that the proportion of T cells expressing each Vβ gene product was similar within CD4+ and CD8+ CD28+ T cells from all samples studied. For these T-cell subsets a rank order of Vβ usage could be identified which was adhered to by all donors. In contrast, within CD8+ CD28- T cells a wide variation of Vβ usage was found between individuals, and no rank order correlation could be detected. Members of HLA identical sibling pairs were found to be no more similar in their usage of Vβ gene products than pairs of HLA disparate random blood donors. Groups of individuals sharing HLA antigens were no different from the groups not sharing such antigens in their usage of Vβ segments. The results suggest that HLA polymorphisms play no more than a minor part in determining TCR Vβ usage. [ABSTRACT FROM AUTHOR]

We have previously described a monoclonal antibody (MoAb), H2, which recognized a tumour-unique antigen on a human T-cell chronic lymphatic leukaemia (T-CLL, CD3,4+). However, further characterization of H2 has revealed a reactivity with the majority of T lymphocytes and a minority of B lymphocytes, some malignant T cells and a few cell lines of leukaemia or of hematopoietic tumour origin. The molecular weight of the antigen (80,000) precipitated by the MoAb H2 from the cell lines NALM-6 and Reh corresponded to that previously found, When PBL were stimulated with PHA, IL-2, or Con A a reduced reactivity of H2 could be seen. The MoAb H2 was submitted to the Fourth International Conference on Human Leucocyte Differentiation Antigens. Vienna, 1989. H2 did not cluster in any of the 78 clusters of differentiation (CD 1-78) discussed at the conference, indicating its unique reactivity. This suggests that we have defined a new antigen on lymphocytes with a possible role along the resting-proliferating axis. [ABSTRACT FROM AUTHOR]

Mouse monoclonal antibodies recognizing cell surface molecules on tumour cells from a patient with a T-cell chronic lymphatic leukaemia (T-CLL) have been produced. Three different types of idiotype-like cell surface structures were identified. Ono molecule had relative molecular weight (Mr) of 90,000 under non-reduced conditions and of 42,000 upon reduction, which corresponds well to the T-cell receptor for antigen (Ti). The two other molecules, which also behaved like unique tumour markers, have not previously been described, to our knowledge. One molecule was a monomer with an Mr of 74,000–80,00 when non-reduced and 80,000 upon reduction. The other idiotypic molecule was a dimer with a non-reduced Mr of 74,000–80,000, and 38,000 after reduction. [ABSTRACT FROM AUTHOR]

We shall demonstrate from examination of vocabulary in several different ecological journals that the terms used by ecologists are in part dictated by the expected audience. The same terms were used in different ways in these different journals. Such linguistic differences could cause serious ambiguity. [ABSTRACT FROM AUTHOR]

Acute renal infarction is a serious medical emergency. The diagnosis is often delayed or missed as it is not common. Hence, the exact incidence of acute renal infarction is not known. Failure to consider renal infarction in the initial differential diagnosis results in a delay in diagnosis and treatment, which in turn leads to permanent loss of renal function. We present two cases of acute kidney infarction that were initially treated as renal colic. In addition, we present a third case when a kidney was saved with reperfusion therapy. [ABSTRACT FROM PUBLISHER]

Knowing how far away animals can detect food has important consequences for understanding their foraging and social behaviors. As part ofa broader set of field experiments on primate foraging behavior, we set out artificial feeding platforms (90 W 90 cm or 50 W 50 cm) throughout the home range of one group of 22 brown capuchin monkeys, at sites where they had not seen such platforms previously. Whenever the group approached such a new platform to within 100 m, we recorded the group's direction and speed of approach, and the identity and distance from the platform of the group member that detected the platform orcame closest to it without detecting it. We used logistic regressionon these data to examine the effects of group movement speed, platform size and height, and focal individual age and sex on the probability of detecting the platform as a function of distance. Likelihood ofdetecting a platform decreased significantly at greater distances - the probability of detecting a platform reached 0.5 at 41 m from the group's center and 25.5 m from the nearest group member. These results show that detectability of platforms by the entire group (9 adults,13 juveniles) was less than twice that for single group members. Detectability at a given distance decreased severely as the group moved faster; at their fastest speed, individuals had to approach a platform to within less than 10 m to find it. The large platforms were significantly more likely to be detected than the small ones, suggesting that increased use of larger food patches by wild primates may not necessarily reflect foraging preferences. [ABSTRACT FROM AUTHOR]

Background: Tissue advanced glycation end products (AGEs) accumulate in chronic kidney disease (CKD) and are a measure of cumulative metabolic stress. Measurement of tissue AGEs by skin autofluorescence (SAF) correlates well with cardiovascular outcomes in dialysis patients. SAF levels in transplant recipients relative to CKD and dialysis patients have not been previously studied, and the impact of transplantation on SAF levels in dialysis patients is unknown., Methods: SAF was measured using an AGE reader in 66 patients who had received a kidney transplant. Values were compared to those obtained in 1,707 patients with CKD stage 3 and in 115 patients on dialysis., Results: Mean SAF in transplant recipients [2.81 ± 0.64 arbitrary units (AU)] was significantly lower than in patients on haemodialysis (3.73 ± 0.88 AU) and peritoneal dialysis (3.57 ± 0.75 AU; p < 0.001), but was no different from CKD stage 3 (2.79 ± 0.66 AU; p = 0.42). In the transplant group, SAF correlated most strongly with age (r = 0.316). There was no correlation between SAF and estimated glomerular filtration rate or renal replacement therapy vintage. A small cohort of patients with SAF recorded on dialysis and following transplantation showed a drop in SAF over a mean time of 16 months after transplantation., Discussion: Tissue AGE values in kidney transplant recipients are significantly lower than in patients receiving dialysis and similar to those in patients with CKD stage 3. Our data suggest that transplantation may be associated with a reduction in tissue AGEs, and this might be an important component of the observed reduction in cardiovascular risk in transplant recipients compared to patients on dialysis., (© 2013 S. Karger AG, Basel.)

We review and discuss the ultimate and proximate causes of birth seasonality in Neotropical primates and the seasonal patterns shown by each genus within this group. Our review of the literature shows that most New World monkey populations studied so far show some degree of birth seasonality. Photoperiod is the most important proximate cue used by populations living at relatively high latitudes to time their reproductive events, but almost nothing is known about the proximate factors used by those near the equator. The findings are consistent with the hypothesis that food availability is the most important ultimate cause of birth seasonality. Predation seems to promote birth synchrony in some species (e.g., squirrel monkeys). Multiple regression ANCOVA was used to estimate how the degree of birth seasonality is affected by ecological and life history variables. The ANCOVA model shows that three factors affect the degree of birth seasonality: diet, latitude, and body size. Folivores (howlers) are less seasonal than frugivores and insectivores. The degree of seasonality increases with latitude and shows a humped relationship with body size, peaking at 1.66 kg body mass. This last relationship was expected since small bodied species have to pay a cost (in terms of time lost) by being seasonal on a yearly basis, and large species are buffered against fluctuations in food availability due to their large body mass. To understand which of three alternative birth strategies is followed by each species (reduce energy stress during peak lactation, wean infants during peak food availability, or store reserves during peak energy availability), we compared the location of the birth peak in relation to the peak in food-availability for those populations from which data were available. Most species conform to the typical pattern of births concentrated before the peak in food availability, allowing peak lactation (small-sized species) or weaning (capuchins) to take place before the start of the lean season. The pattern of births of the atelines is consistent with the weaning hypothesis. However, since they give birth during the lean season, this pattern is also consistent with an alternative strategy.

The T cell receptor (TCR) variable (V) gene repertoire was analyzed in patients with monoclonal gammopathy of undetermined significance (MGUS) (n = 17), multiple myeloma (MM) stage I (n = 16), MM stages II/III (n = 31) and age-matched controls (n = 27) by immunofluorescence and flow cytometry using a panel of mouse monoclonal antibodies (mAb) (n = 10) against TCR V alpha and V beta gene products. T cell expansion was defined as a value > or = thrice the normal median value for each respective TCR V mAb. Fifty-three percent of all patients displayed CD8+ expansion(s) as compared to 30% of age-matched controls (p < 0.001). Within the CD4 subset, 18% of the patients displayed T cell expansion(s) in comparison to 11% of the controls (not significant). Interestingly, the CD8+ expansion(s) were more frequently noted in patients with a low tumor burden (MGUS/MMI) (73%) as compared to those with advanced disease (MM II/III) (32% and control donors (30%) (p < 0.01). Likewise, multiple CD8+ expansions (two or more) were more common in MGUS/MM I patients than in MM II/III and controls (p < 0.01). The T cell expansions were stable over time in patients with a stable disease. A high degree of clonality of the expansions was detected by TCR CDR3 fragment length analysis, determination of J beta gene usage and nucleotide sequencing. The frequent finding of oligoclonal CD8+ T cell expansions in patients with a low tumor mass, but not in patients with advanced disease justifies further work in order to identify the relevance of expanded CD8+ T cells. In one patient with T cell reactivity against the autologous myeloma idiotype, two expansions within the CD8 population (V beta 3 and V beta 5.2 respectively) displayed no reactivity against the idiotype. Instead, idiotype recognition was confined to a CD8 non-expanded V beta 22+ T cell population, with a highly restricted TCR usage (CDR3 fragment length analysis).

In order to investigate the T-cell receptor (TCR) V beta usage in different T-cell subsets, the authors performed flow cytometric analyses using a large panel of TCR V beta-specific monoclonal antibodies on CD4+, CD8+ CD28+ and CD8+ CD28- T cells from 15 random blood donors, six umbilical cords and seven human leucocyte antigen (HLA) identical non-twin sibling pairs. The authors found that the proportion of T cells expressing each V beta gene product was similar within CD4+ and CD8+ CD28+ T cells from all samples studied. For these T-cell subsets a rank order of V beta usage could be identified which was adhered to by all donors. In contrast, within CD8+ CD28- T cells a wide variation of V beta usage was found between individuals, and no rank order correlation could be detected. Members of HLA identical sibling pairs were found to be no more similar in their usage of V beta gene products than pairs of HLA disparate random blood donors. Groups of individuals sharing HLA antigens were no different from the groups not sharing such antigens in their usage of V beta segments. The results suggest that HLA polymorphisms play no more than a minor part in determining TCR V beta usage.

This paper gives an overview of the biology of monoclonal antibodies in tumor therapy. The complexity of the monoclonal antibody concept is discussed with functional aspects on tumor antigen, antigen binding, Ig isotypes and effector mechanisms involved.

In addition to being frugivorous, Cebus and Saimiri stand out among the New World primates of similar body size in being heavily dependent on animal matter for protein (faunivory). A detailed description of the morphology and behavior of the two genera is presented with the object of evaluating the interaction and respective contributions of morphological and behavioral adaptations to foraging patterns. Our conclusions include the following: First, body size is extremely important in explaining the observed variation in diet. Second, the emphasis on faunivory is facilitated more by behavioral than by morphological specialization. Third, whatever morphological specializations are present, particularly in Cebus, are probably favored by diet at the most food-depauperate time of year. Fourth, although morphology may well reveal what a primate may potentially eat, to map this potential onto actual diet requires a detailed knowledge of its natural ecosystem. Finally, we consider whether the behavioral data support the tenuous morphological evidence for grouping Cebus and Saimiri within the clade Cebinae.

Certain T cell antigen receptor V gene products in man have been shown by us and others to display a reproducible bias for preferential expression in CD4+ or CD8+ T cell subsets. In order to investigate whether such a skewed representation of V gene segments is also present at the J gene segment level, we tested the relative J beta gene usage by V beta 5.1 + T cells, as this V beta gene is biased towards CD4+ T cell expression in virtually all individuals. To analyze the usage of the 13 J beta gene segments, we developed a new approach using V beta 5.1 and C beta specific oligonucleotides as 5' and 3' primers respectively for polymerase chain reaction (PCR) amplification of cDNA derived from CD4+ or CD8+ peripheral blood lymphocyte (PBL) T cells. The PCR products were visualized for reactivity with individual J beta 1.1-1.6 and J beta 2.1-2.7 32P-labelled oligonucleotide probes using autoradiography and quantitative gel-scanning. Eleven normal blood donors provided the PBL T cells. The results showed that in every individual's V beta 5.1+ T cell populations (CD4 and CD8), all V beta/J beta combinations were used although at varying but reproducible levels for each J beta gene. Thus, no discernible disallowance of combinations existed. Moreover, we could show that six of 13 J beta genes were unequally expressed when compared in pairs with regard to expression in CD4+ and CD8+ T cell subsets.(ABSTRACT TRUNCATED AT 250 WORDS)

A panel of monoclonal antibodies specific for TcR V gene families was used to study TcR V region expression in 28 cases of malignant and reactive T-cell expansions including four cases of mixed cellularity Hodgkin's disease (HD) and five reactive cases. TcR V beta 5 gene products were represented in three cases of lymphoblastic malignancy (V beta 5.1, V beta 5.2) and two cases of peripheral T-cell lymphoma (PTCL) (V beta 5.1). In the PTCL cases, the expanded family was found in the absence of clonal TcR gene rearrangements and in one of these cases with Ig JH and Ck clonal gene rearrangements consistent with the presence of a phenotypically and histologically undetectable clonal B-cell population. In a third PTCL case not investigated for genotype, the TCR V alpha 12 family was overrepresented. Expanded TcR V alpha 2 and V beta 5.1 families were identified in HD and V beta 8 and V beta 5.2/V beta 5.3 families in a reactive lymph node and CD3 and CD8-positive blood lymphocytosis respectively. Further study of PTCL and related entities are needed to establish whether expanded TcR families are common in those cases that fail to exhibit clonal TcR gene rearrangement.

The alpha/beta T cell receptor (TcR) V gene usage of bronchoalveolar lavage (BAL) lymphocytes and peripheral blood lymphocytes (PBL) from 11 sarcoidosis patients and 4 healthy controls was investigated, using eight alpha/beta TcR V gene product-specific monoclonal antibodies (mAb). Twenty-seven percent (3/11) of the sarcoidosis patients had a highly significant increase in V alpha 2.3+CD4+ T lymphocytes in the bronchoalveolar space, while displaying normal frequencies of these T cells in peripheral blood. The reactivities with the remaining seven TcR mAb were normal. In the control group, no compartmentalization of any T cells was seen. Four of the patients expressed the HLA-DR3 (w17), DQw2 haplotype. Interestingly, the three patients with distinct signs of compartmentalized V alpha 2.3+CD4+ T cells all expressed this HLA haplotype. Additionally, a fourth patient with pronounced, although less significant, accumulation of V alpha 2.3+CD4+ T cells in the lung, was also HLA-DR3(w17), DQw2+. Expression of V alpha 2.3+CD4+ T cells in BAL of these patients correlated with clinical disease, as revealed on re-analyzing the four patients after 6 months or longer. Predominant TcR V alpha 2.3 gene usage in compartmentalized CD4+ BAL T lymphocytes, linked to HLA-DR3(w17), DQw2 haplotype, may thus indicate presence of a specific antigen localized to the lungs of sarcoidosis patients.

We have previously analysed alpha/beta T cell receptor (TCR) V gene usage in CD4+ and CD8+ subpopulations from human peripheral blood lymphocytes (PBL) and umbilical cord blood, and described a biased usage of some of the TCR V beta genes towards the CD4+ subpopulation. In this report, the TCR V gene usage in single positive (SP) CD4+ or CD8+ human thymocytes was analysed. Three previously described mAb with a biased usage in PBL and umbilical cord blood also had a skewed reactivity towards the CD4+ subpopulation in SP human thymocytes. Thus, in all 12 cases V beta 5.1 and V beta 6.7, and in 11/12 cases V beta 12 were preferentially used in the CD4+CD8-, compared to the CD4-CD8+ thymic subpopulation. Altogether, these results suggest a selection process in the thymus, supposedly through the positive influence of MHC class II determinants, to be responsible for this non-random, skewed TCR V gene usage.

We have examined alpha/beta V gene segment usage of peripheral blood CD4+ and CD8+ T cells, respectively, from patients with multiple myeloma and monoclonal gammopathy of undetermined significance, by using T cell receptor (TCR) for antigen monoclonal antibodies (MoAbs). In 7 of 16 patients we found an increase in the usage of various TCR V gene segments. The expansion was confined to either the CD4+ or the CD8+ T-cell subset, except for one patient where an abnormal pattern was observed both within the CD4+ and CD8+ T-cell subsets. In one patient 47%, and in another patient 30% of the CD8+ lymphocytes reacted with alpha V12.1 and beta V6.7 antibodies, respectively. In two other patients 29% and 40% of the CD4+ lymphocytes reacted with beta V6.7 and beta V8.1 antibodies, respectively. We conclude that T cells with a predominant V gene usage is a frequent feature in patients with abnormal clonal B cells of malignant or benign types. T- and B-cell populations are normally clonally linked in regulatory circuits. An abnormal proliferation of B cells might therefore induce, or be regulated by, an expansion of clonal T cells, as suggested by the present results.

The expression of seven different alpha and beta gene segments of the T cell receptor on normal human CD4+ and CD8+ T lymphocytes, respectively, was examined using V gene-specific monoclonal antibodies. We found a statistically significant (p less than 0.001) bias of the expression of four V gene products towards the CD4+ subpopulation. In every individual analyzed, the V beta 5.1 gene segment was expressed to a higher degree among CD4+ compared to CD8+ cells, with a median value of 4.8% among CD4+ cells and 1.5% among CD8+ cells. There was also a statistically significant skewness in the usage of the V beta 6.7, V beta 8 and V beta 12 gene segments towards the CD4+ T cell population, but not as dominating as for the V beta 5.1. Lymphocytes from umbilical cord blood showed similar skewed reactivities for the V beta 5.1, V beta 6.7 and V beta 12-specific monoclonal antibodies. Aspects of positive and negative selection, as possible explanations for these findings, are discussed.