Pleistocene to recent dietary shifts in California condors.

We used carbon and nitrogen isotopes to investigate changes in the diet of California condors from the Pleistocene to the recent. During the Pleistocene, condors from California fed on both terrestrial megafauna and marine mammals. Early accounts reported condors feeding on the carcasses of marine mammals, but by the late 1700s, condor diets had shifted predominantly to terrestrial animals, following the commercial harvesting of marine mammals and the development of cattle ranching on land. At present, dairy calves provided by humans significantly augment condor diet, constituting an artificial support of the current population. Reestablishing a marine mammal component in the condor diet may be an effective strategy for fostering viable condor populations independent of direct human subsidies.

Interferon regulatory factor expression in human breast cancer.

OBJECTIVE: To investigate the expression of interferon regulatory factors 1 and 2 (IRF-1 and IRF-2) in human breast cancer. SUMMARY BACKGROUND DATA: Interferon regulatory factors 1 and 2 are transcription factors in the interferon gamma signal transduction pathway. IRF-1 acts as the effector arm of the interferon gamma response; IRF-2 binds to the same DNA consensus sequence and opposes IRF-1 activity. Previous work in the authors' laboratory has shown the tumor suppressor activity of IRF-1 expression and the oncogenic effect of IRF-2 in human and murine tumor models, including human breast cancer cell lines. The authors' hypothesis is that this pathway is involved in human tumor development, and alterations in the expression of IRF-1 and IRF-2 may occur in breast cancer tissue compared with normal breast tissue, and between more and less differentiated breast cancers. METHODS: Formalin-fixed paraffin-embedded human archival tissue specimens were obtained from 33 patients with pure ductal carcinoma in situ (DCIS) and 49 women with invasive ductal cancer. Adjacent areas of normal breast tissue were assayed in 31 women. These specimens were stained with polyclonal IRF-1 and IRF-2 antibodies using an avidin-biotin-peroxidase complex technique after epitope retrieval. RESULTS: Most normal breast tissue showed expression of IRF-1 and no expression of IRF-2 by immunohistochemistry. High-grade DCIS or node-positive invasive ductal cancers were less likely to express the tumor suppressor IRF-1 than normal tissue. More strikingly, high-grade DCIS and invasive ductal cancers were much more likely to express the oncogenic IRF-2 protein than was normal tissue. CONCLUSIONS: Expression of IRF-1 and IRF-2 is altered in human breast cancer compared with normal adjacent tissue. The loss of IRF-1 expression is consistent with tumor suppressor loss and the development of IRF-2 expression with oncogenic activation. These data support the hypothesis that this pathway is involved in human breast oncogenesis, which warrants further investigation regarding prognostic and therapeutic implications.

Calbindin immunoreactivity in the geniculo-extrastriate system of the macaque: implications for heterogeneity in the koniocellular pathway and recovery from cortical damage.

Although most projection neurons in the primate dorsal lateral geniculate nucleus (dLGN) target striate cortex (V1), a small number project instead to extrastriate visual areas and have been suggested to play a role in the preserved vision ("blindsight") that survives damage to V1. Moreover, the distribution of dLGN cells projecting to extrastriate bears a striking similarity to that of neurons that stain for calbindin D-28K (Cal), a calcium-binding protein involved in regulating neuronal excitability and considered a marker for the koniocellular or "K" pathway of geniculocortical processing. In these studies, we used double-labeling techniques to examine whether Cal content characterizes all or a subset of neurons making up the geniculo-extrastriate pathway in normal macaque monkeys. After injections of cholera toxin B-subunit into the prelunate gyrus, the proportion of retrogradely labeled neurons in the dLGN that were also immunoreactive for Cal varied from less than 40% to over 80%, indicating that only a subset of the geniculo-extrastriate projection falls within the K pathway as defined by Cal content. Analysis of the injected territories indicated that identity of the extrastriate cortical target may be systematically related to Cal content in the geniculo-extrastriate projection. To see whether the Cal-immunoreactive dLGN population might potentially play a role in preserved vision after V1 damage, we also examined the dLGN of a macaque that had sustained a lesion of V1 in infancy and survived until 4 years. In this animal, large, intensely Cal-immunoreactive neurons were found scattered throughout the otherwise degenerated dLGN zones and made up over 95% of the identifiable remaining neurons. The results support an emerging view that the macaque koniocellular system is highly heterogeneous in nature and also suggest that Cal content may be a critical feature of the pathway by which visual information reaches extrastriate cortex in the absence of V1.

Predisposition to urinary tract epithelial metaplasia in Schistosoma haematobium infection.

Although there is strong epidemiologic evidence linking Schistosoma haematobium infection with carcinoma of the bladder, the utility of cytologic screening for urinary tract cancer has not been critically evaluated in S. haematobium-endemic populations. The present cross-sectional study examined urine cytology findings among 1,014 residents (ages 1 to 91) of the S. haematobium-endemic Msambweni area of Coast Province, Kenya. Among 705 evaluable cytology specimens, prevalence of inflammation (39%), hyperkeratosis (30%), metaplasia (33%), and frank atypia (0.4%) was notably higher than in previously studied, non-endemic populations. Overall, S. haematobium infection was strongly associated with increased risk for cytologic abnormality (> 2.8-fold relative risk of metaplasia or hyperkeratosis; P < 0.001). Age-group analysis confirmed parallel increases in metaplasia and S. haematobium infection prevalence early in life (from age I to 15 for both boys and girls). However, above age 20, metaplasia prevalence persisted at 33-45% prevalence despite a decline in infection prevalence and intensity. Prevalence of advanced (moderate or severe) metaplasia showed two age-related peaks: the first at 10-14 years of age (at the time of peak infection), and the second among subjects > or = 60 years old. No cancers were detected in the study population either on cytology or on follow-up ultrasound examination. These data suggest an age-dependent progression of cellular abnormalities in the urinary epithelium that is associated with chronic S. haematobium infection, which becomes independent of concurrent infection intensity as subjects grow older. Implications for cancer screening are discussed.

A transient geniculo-extrastriate pathway in macaques? Implications for 'blindsight'.

Both monkeys and cats receiving primary visual cortex lesions in infancy show better residual vision than animals sustaining similar damage in adulthood. In cats, the better recovery has been explained in part by stabilization of a transient pathway from the dorsal lateral geniculate nucleus (dLGN) to cortical visual area PMLS. To test the hypothesis that a similar transient pathway from the dLGN to dorsal extrastriate areas exists in primates and thus serves as a candidate for recruitment after early V1 damage, retrograde tracers were injected into areas MT, MST, and/or 7a of infant macaques. No evidence of a transient pathway from the dLGN to these areas was obtained, despite projections from the pulvinar and other extrastriate areas in all cases.

The lateral geniculate nucleus does not project to area TE in infant or adult macaques.

We sought to determine if there are any direct projections from the dorsal lateral geniculate nucleus (dLGN) to visual cortical area TE in either adult or infant primates. To do so, we examined labelling in the thalamus of eight macaque monkeys which received injections of the retrograde tracer cholera toxin-B subunit within TE. Four of these cases were infants in which the injections revealed transient patterns of inputs to TE from various other brain regions. Although each monkey showed extensive label in the pulvinar nucleus and other subcortical structures, none showed unambiguous labelling in the dLGN. The absence of direct connections between the dLGN and area TE indicates that rudimentary color and form processing capacities in the absence of striate cortex must utilize other pathways even when damage to striate cortex takes place early in life.

Long-term results of Charnley total hip replacement. Review of 92 patients at 15 to 20 years.

We made a prospective study of 241 Charnley total hip replacements performed between 1968 and 1974. In 1990, we reviewed 92 patients with 103 hips (96.3% of surviving hips) at a mean follow-up of 17.6 years (15 to 20.6) The clinical results were excellent, with Charnley scores of 4 or more for pain in 95% of the patients, for function in 73% and for movement in 93%. Of the whole series, 8.3% had been revised, and Kaplan-Meier survival analysis showed a probability of revision at 20 years of 10.7%. These results are similar to those from the few other series with extended follow-up, and make it difficult to justify the present widespread use of uncemented hip prostheses. It would seem that some aspects of the design of the first-generation Charnley stem were beneficial for long-term survival of the arthroplasty. We found no correlation between the clinical results and radiological loosening on the Harris scale.

Small cell carcinoma of the genitourinary tract: an immunohistochemical, electron microscopic and clinicopathological study.

We examined 13 cases of small cell carcinoma of the genitourinary tract to evaluate and compare the immunocytochemical and ultrastructural features as well as the clinicopathological behavior. Immunohistochemical stains revealed that neuron specific enolase and chromogranin showed differences in staining between the bladder and prostate, as well as between the small cell and adenocarcinomatous components of the prostate. Also, synaptophysin was negative over-all in 12 of 13 cases. Epithelial membrane antigen, carcinoembryonic antigen and keratin showed strong focal positivity within the small cell component. Electron microscopy was performed in 4 cases, with 3 demonstrating neurosecretory granules. Clinically, 6 of the 7 patients with adenocarcinoma/small cell carcinoma of the prostate did poorly, all with a survival of 15 months or less. Of 5 patients with transitional cell/small cell carcinoma of the bladder 2 fared better (both had no evidence of disease at 12 months and 11 years, respectively). Based upon the immunostaining and electron microscopic findings, small cell carcinoma of the genitourinary tract is heterogeneous in appearance and, therefore, may arise from a multipotential cell of origin. This cell of origin may be organ-specific, as demonstrated by the variability in staining characteristics among the prostate, bladder and kidney, as well as by the differences in the clinical behavior of these malignancies. Small cell carcinoma of the prostate has a poor prognosis, while small cell carcinoma of the bladder may portend a better prognosis if diagnosed at an early stage.

Computed tomography-guided retroperitoneal biopsies.

A retrospective review was performed on consecutive patients who had a computed tomographic (CT) biopsy of the retroperitoneum at University Hospitals of Cleveland. Biopsies were performed using a 20-gauge Chiba needle (University Medical Instruments Corp, Ballston Spa, NY) and a 14-gauge Tru-Cut needle (Baxter Pharmaseal, Valencia, CA). The results included success rate, failure, and complications, and were determined by a review of patient charts, surgical results, and autopsy results. The 20-gauge needle aspirations were accurate in suggesting the diagnosis in 20 of 22 cases of metastatic disease and ten of 15 cases of lymphoma. Using the 20-gauge needle, it was not possible to make a specific diagnosis in any of the lymphoma patients or for unusual benign disorders. With the 14-gauge Tru-Cut needle, the correct diagnosis was made in 13 of 13 cases of metastatic disease, ten of 11 cases of lymphoma, and two of 2 cases of unusual benign disorders. It was also possible to make the specific diagnosis of the lymphoma type in ten of 11 cases. The only complication was a small subcutaneous hematoma following a biopsy with a 20-gauge Chiba needle.

Important time, though not causal, relations in atrial natriuretic peptide, cortisol and renin.

A cosinor analysis validates a circadian rhythm in circulating atrial natriuretic peptide and quantifies its time relations to circulating cortisol and renin.

Escherichia coli serogroups in breast-fed and bottle-fed infants.

1) Eighty-seven breast-fed and 95 bottle-fed infants were examined for differences in Escherichia coli serogroup pattern. 2) The serogroup composition was less complex in breast-fed infants. Fewer serogroups were found in the individual breast-fed child. However, with few exceptions, the same O groups were found in the two groups of infants. The prevalent O groups were among those also found most frequently in faeces from adults. 06 strains were more common in the breast-fed group, while 07 and 016 were not at all found in that group. 3) A special search for E. coli strains with Kl antigen showed that this antigen predominated in the bottle-fed infants. 4) Klebsiella and other Enterobacteriaceae were more frequently found among bottle-fed infants. 5) It is concluded that the intestinal milieu exerts a selective pressure which may result in a selection of different serotypes in two different intestinal milieus such as those examined.