Clonal chromosome abnormalities in human breast carcinomas I. Twenty-eight cases with primary disease

Cytogenetic analysis was performed on a selected series of short-term cultures of primary breast carcinomas from 28 patients. All patients had histopathologically confirmed malignancies, with the majority (25/28 cases) demonstrating infiltrating ductal carcinoma. All 28 cases evidenced clonal chromosome abnormalities, with 10/28 displaying only numeric aberrations, whereas 18/28 displayed clonal structural alterations. In near-diploid tumors the most common numeric changes were — 17 and — 19. However, trisomy 7 was the only numeric change in two near-diploid tumors. Structural chromosome alterations were primarily isochromosomes, apparent terminal deletions, and unbalanced non-reciprocal translocations. Chromosomes 1 (10/18–56%) and 6 (8/18–44%) were most frequently altered in this series. Breakpoints of clonal structural abnormalities were shown to cluster to several chromosome segments, including 1p22-q11, 3p11, 6p11–13, 7p11-q11, 8p11-q11, and 19q13. Analysis of the gain or loss of specific chromosome segments revealed that the most consistent tendency was over-representation of 1q, 3q, and 6p. © 1993 Wiley-Liss, Inc.     

Detection of enzootic babesiosis in baboons (Papio cynocephalus) and phylogenetic evidence supporting synonymy of the genera Entopolypoides and Babesia

Blood smear evaluation of two baboons (Papio cynocephalus) experiencing acute hemolytic crises following experimental stem cell transplantation revealed numerous intraerythrocytic organisms typical of the genus Babesia. Both animals had received whole-blood transfusions from two baboon donors, one of which was subsequently found to display rare trophozoites of Entopolypoides macaci. An investigation was then undertaken to determine the prevalence of hematozoa in baboons held in our primate colony and to determine the relationship, if any, between the involved species. Analysis of thick and thin blood films from 65 healthy baboons (23 originating from our breeding facility, 26 originating from an out-of-state breeding facility, and 16 imported from Africa) for hematozoa revealed rare E. macaci parasites in 31%, with respective prevalences of 39, 35, and 12%. Phylogenetic analysis of nuclear small-subunit rRNA gene sequences amplified from peripheral blood of a baboon chronically infected with E. macaci demonstrated this parasite to be most closely related to Babesia microti (97.9% sequence similarity); sera from infected animals did not react in indirect fluorescent-antibody tests with Babesia microti antigen, however, suggesting that they represent different species. These results support an emerging view that the genus Entopolypoides Mayer 1933 is synonymous with that of the genus Babesia Starcovici 1893 and that the morphological variation noted among intracellular forms is a function of alteration in host immune status. The presence of an underrecognized, but highly enzootic, Babesia sp. in baboons may result in substantial, unanticipated impact on research programs. The similarity of this parasite to the known human pathogen B. microti may also pose risks to humans undergoing xenotransplantation, mandating effective screening of donor animals.     

Hemokinin is a hematopoietic-specific tachykinin that regulates B lymphopoiesis

We report here the molecular cloning of a newly identified preprotachykinin gene, Pptc, which specifies the sequence for a new preprotachykinin protein and bioactive peptide designated hemokinin 1 (HK-1). PPT-C mRNA was detected primarily in hematopoietic cells in contrast to the previously described Ppta and Pptb genes, which are predominantly expressed in neuronal tissues. HK-1 has several biological activities that are similar to the most studied tachykinin, substance P, such as induction of plasma extravasation and mast cell degranulation. However, HK-1 also has properties that are indicative of a critical role in mouse B cell development. HK-1 stimulated the proliferation of interleukin 7-expanded B cell precursors, whereas substance P had no effect. HK-1, but not substance P, promoted the survival of freshly isolated bone marrow B lineage cells or cultured, lipopolysaccharide-stimulated pre-B cells. N-acetyl-L-trytophan-3,5-bistrifluromethyl benzyl ester, a tachykinin receptor antagonist, increased apoptosis of these cells and in vivo administration of this antagonist led to specific reductions of the B220lowCD43 population (the pre-B cell compartment) in the bone marrow and the IgMhighIgDlow population (the newly generated B cells) in the spleen. Thus, HK-1 may be an autocrine factor that is important for the survival of B cell precursors at a critical phase of development.     

Compounding Stress: Childhood Adversity as a Risk Factor for Adulthood Trauma Exposure in the Health and Retirement Study

Childhood adversity (CA) and adulthood traumatic experiences (ATEs) are common and unequally distributed in the general population. Early stressors may beget later stressors and alter life‐course trajectories of stressor exposure. Gender differences exist regarding the risk of specific stressors. However, few studies have examined the associations between specific types of CA and ATEs. Using a large‐scale sample of older adults, we aimed to (a) determine if specific or cumulative CA increased the risk for specific or cumulative ATEs and (b) examine whether these associations were moderated by gender. In a sample from the U.S. Health and Retirement Study (N = 15,717; M_age = 67.57 years, SD = 10.54), cross‐sectional Poisson and logistic regression models were fitted to assess the specific and cumulative associations between CA and ATEs. Overall, cumulative CA was associated with a larger risk ratio of ATEs, adjusted for covariates: aRRRs = 1.28, 1.63, and 1.97 for 1, 2, and 3–4 adverse events in childhood, respectively. Cumulative CA was particularly strongly associated with adulthood physical attacks, aOR = 5.66, and having a substance‐abusing spouse or child, aOR = 4.00. Childhood physical abuse was the strongest independent risk factor for cumulative ATEs, aRRR = 1.49, and most strongly associated with adulthood physical attacks, aOR = 3.41. Gender moderated the association between cumulative CA and cumulative ATEs, with slightly stronger associations between cumulative CA and ATEs for women than men. Given that CA and ATEs perpetuate health disparities worldwide, reducing their incidence and effects should be major priorities for public health.     

Bolus versus continuous feeding regimens post gastrostomy tube placement in children

Background/purposeOwing to the frequency of gastrostomy tube placement in children and the numerous regimens used to start feeds after placement we attempted to see if it matters if the initial feeds after a gastrostomy tube placement are provided in a bolus or continuous manner.MethodsUsing a prospective randomized trial, children were randomized to initial bolus or continuous chimney feeding after gastrostomy tube placement. Feeding tolerance and complications related to the gastrostomy tube were collected for 4 weeks after placement.ResultsDemographics were similar in the two groups. Times to goal feeds were similar in both groups, but in the first two weeks more feeding modifications were required in the bolus group. Other than the rate of leakage during the second week after placement which occurred more in the bolus group, all other clinical outcomes were similar in the two groups.ConclusionsOther than minor, clinically insignificant differences noted above, the method of initial feeding after a gastrostomy tube placement does not affect feeding tolerance or gastrostomy tube complication in the first month after placement.Level of evidenceTherapeutic, level II.     

Spatial and temporal receptive-field analysis of the cats geniculocortical pathway

Receptive field (RF) properties of lateral geniculate (LGN) and cortical visual neurons were studied in cats using computer-controlled bar and edge stimuli. Responses to stationary presentations of an optimally oriented bright bar in an array of closely spaced RF positions provided detailed spatial and temporal information about RFs. Moving edge stimuli represent a more nearly normal viewing situation, and responses provide additional information for classifying RFs. Our results allow inferences about the nature of input connections to conical units. Responses of simple striate cells and X cells of LGN were similar to each other and quite different from those of complex and Y-LGN cells. Simple and X cells exhibited spatially segregated regions of excitation and inhibition and large shifts in response latency as a function of stimulus position. Both cell types showed spatially nonoverlapping regions of response (discharge zones) to moving bright and dark edges. These results provide correlational evidence that simple cells of striate cortex receive input predominantly from X-LGN cells. X-LGN cells respond to increases or decreases in local stimulus flux, depending on stimulus position, and via separate (from segregated RF areas) projections to the cortex determine contrast polarity of the cortical response. Complex cells, on the other hand, exhibited transient responses to both stimulus onset and removal. with a constant response latency across the entire RF. Results from the same test on Y-LGN cells were strikingly similar to those for complex cortical cells. However, complex cells show far more overlap in edge discharge zones than either on- or off-center Y-LGN cells. This comparison suggests spatially overlapping input to complex cells from both on-and off-center Y-LGN cells. A third type of cortical cell (in area 18) demonstrated edge and static-bar responses that strongly resembled those of either on-or off-center Y-LGN cells. Input to these parastriate cortical cells apparently derives from either on-or off-center Y-LGN cells. We believe that these units represent the parastnate equivalent of striate simple units in that they seem to receive inputs from spatially segregated RF areas, in this case of Y-LGN units.     

Failure mechanisms of unicompartmental knee replacement: the impact of changes in operative technique and component design

Reliable unicompartmental knee replacement requires knowledge of the common failure mechanisms of this type of arthroplasty. The problem in the past has been loosening of components because of design flaws and technical failure. Whereas recent reports are very encouraging in terms of clinical results and enhanced durability of unicompartmental replacements, the current study confirms the observation that nonparallel orientation of femoral and tibial components is common and may produce excessive polyethylene wear and clinical failure. Newer unicompartmental designs with meniscal bearings may be the answer to this problem.     

Restoration of bone stock in revision surgery of the femur

Three hundred and four femoral revisions were performed from 1987 to the end of 1990. All were done with cementless titanium calcar replacement prostheses, designed for proximal bone loading. Type III bone deficiencies were present in 160 femurs, all requiring supplemental cortical bone plates for bony augmentation. All grafts united and provided increased bone stock in the long term. Physiologic loading is important for graft remodeling and maturation. Hip scores have improved from an average Harris Hip Score of 44 to 84. Current survivorship at 10 years is 96%, and the revision rate is 3.2%. Thigh pain is mild in 3% of cases. There have been no late failures or distal lysis noted to date.

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Résumé  De 1987 à 1990, on a procédéà 304 reprises de prothèse totale de hanche (PTH) associées à des implants fémoraux standard en alliage de titane non cimentés et spécifiquement étudié et réalisés pour bien s’adapter à la morphologie osseuse et à la résistance mécanique proximale. 160 cas de fémur nécessitèrent – vu la présence de perte de sustance osseuse de type III – la mise en place sur la corticale de plaque osseuse de remplacement afin d’augmenter et la repousse fémorale osseuse. On observe dans les cas de reprise de PTH, une amélioraton du recul moyen: ce dernier passait de 44 mois (selon l’échelle de le Harris Hip score) à 84 mois. A l’heure actuelle, le taux actuariel de survie des implant est de 96% à 10 ans avec un taux de reprise de 3.2%. On note la presence de douleur à la cuisse dans 3% des cas, mais à l’heure actuelle, on ne rapporte aucun échec tardif ni osteolyse distale.

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Accepted: 7 December 1999     

Minority recruitment in hereditary breast cancer research.

Although recruitment of ethnic and racial minorities in medical research has been evaluated in several studies, much less is known about the methods used to recruit these populations to participate in cancer genetics research. This report reviews the resources that have been used to identify and recruit ethnic and racial minorities to participate in hereditary breast cancer research. Overall, hospital-based resources were used most often to identify potential subjects, and active recruitment methods were used most frequently to enroll eligible subjects. This review suggests that there appears to be a finite number of resources and strategies to identify and recruit potential subjects to participate in cancer genetics research; however, options for improving awareness about cancer genetics research among ethnic and racial minorities have not been extensively evaluated. To study ethnic and racial minority participation in cancer genetics research, stronger evaluation components will need to be integrated into research methods. Both observational and experimental studies are needed to determine resources that are most effective for identifying potential subjects who are ethnic and racial minorities and to evaluate the effects of different recruitment strategies on enrollment decisions among these populations.