Male pseudohermaphroditism caused by mutations of testicular 17 beta-hydroxysteroid dehydrogenase 3.

Defects in the conversion of androstenedione to testosterone in the fetal testes by the enzyme 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) give rise to genetic males with female external genitalia. We have used expression cloning to isolate cDNAs encoding a microsomal 17 beta-HSD type 3 isozyme that shares 23% sequence identity with other 17 beta-HSD enzymes, uses NADPh as a cofactor, and is expressed predominantly in the testes. The 17 beta HSD3 gene on chromosome 9q22 contains 11 exons. Four substitution and two splice junction mutations were identified in the 17 beta HSD3 genes of five unrelated male pseudohermaphrodites. The substitution mutations severely compromised the activity of the 17 beta-HSD type 3 isozyme.

Large clonal expansions of CD8+ T cells in acute infectious mononucleosis.

Primary infection with Epstein-Barr virus often results in the clinical syndrome of acute infectious mononucleosis (glandular fever). This illness is characterized by a striking lymphocytosis, the nature of which has been controversial. We show that large monoclonal or oligoclonal populations of CD8+ T cells account for a significant proportion of the lymphocytosis and provide molecular evidence that these populations have been driven by antigen. The results suggest that the selective and massive expansion of a few dominant clones of CD8+ T cells is an important feature of the primary response to this virus.

Direct visualization of antigen-specific CD8+ T cells during the primary immune response to Epstein-Barr virus In vivo.

Primary infection with virus can stimulate a vigorous cytotoxic T cell response. The magnitude of the antigen-specific component versus the bystander component of a primary T cell response remains controversial. In this study, we have used tetrameric major histocompatibility complex-peptide complexes to directly visualize antigen-specific cluster of differentration (CD)8+ T cells during the primary immune response to Epstein-Barr virus (EBV) infection in humans. We show that massive expansion of activated, antigen-specific T cells occurs during the primary response to this virus. In one individual, T cells specific for a single EBV epitope comprised 44% of the total CD8+ T cells within peripheral blood. The majority of the antigen-specific cells had an activated/memory phenotype, with expression of human histocompatibility leukocyte antigen (HLA) DR, CD38, and CD45RO, downregulation of CD62 leukocyte (CD62L), and low levels of expression of CD45RA. After recovery from AIM, the frequency of antigen-specific T cells fell in most donors studied, although populations of antigen-specific cells continued to be easily detectable for at least 3 yr.

Oligoclonal expansions of CD8(+) T cells in chronic HIV infection are antigen specific.

Acute HIV infection is associated with a vigorous immune response characterized by the proliferation of selected T cell receptor V beta (BV)-expressing CD8(+) T cells. These 'expansions', which are commonly detected in the peripheral blood, can persist during chronic HIV infection and may result in the dominance of particular clones. Such clonal populations are most consistent with antigen-driven expansions of CD8(+) T cells. However, due to the difficulties in studying antigen-specific T cells in vivo, it has been hard to prove that oligoclonal BV expansions are actually HIV specific. The use of tetrameric major histocompatibility complex-peptide complexes has recently enabled direct visualization of antigen-specific T cells ex vivo but has not provided information on their clonal composition. We have now made use of these tetrameric complexes in conjunction with anti-BV chain-specific monoclonal antibodies and analysis of cytotoxic T lymphocyte lines/clones to show that chronically clonally expanded CD8(+) T cells are HIV specific in vivo.

Ammonia emissions from broiler production in the San Joaquin Valley.

Ammonia is the primary basic gas in the atmosphere and has the most important role in the neutralization of atmospheric acids generated by fossil fuel combustion. The reaction product forms a NH(4)(+) aerosol, which is a major component of atmospheric particulates. These NH(4)(+) particulates are part of atmospheric haze and may be transported long distances from the production site before returning to the surface by dry deposition or scavenged by precipitation. Animal production produces a significant component of anthropogenic NH(3) emissions and the National Academy of Sciences concluded that NH(3) emissions estimates from animal feeding operations have not been characterized sufficiently, leading the US Environmental Protection Agency to institute studies in the United States to obtain NH(3) emissions from animal feeding operations under the US Environmental Protection Agency Air Consent Agreement. The objective of this study is to obtain additional broiler NH(3) emissions estimates using a backward Lagrangian stochastic technique. This technique uses NH(3) concentrations measured upwind and downwind of the farm, wind observations, and atmospheric dispersion model calculations to obtain whole-farm emissions. Ammonia emissions were low at bird placement and increased steadily after about the third week of growth. At the end of the flock (47 d, ~297,000 birds), cumulative emissions for the flock cycle period were 0.016 kg of NH(3).bird(-1).flock(-1). Between-flock emissions, including bird harvest, cleanout, temporary storage of litter outside of the buildings, and downtime (buildings closed), added another 0.003 kg of NH(3).bird(-1).flock(-1). Emissions from this broiler farm were less than from some eastern US broiler farms but were comparable to broiler farms in Europe. Based on the results of this study and a similar winter study at this same farm, total flock wintertime and summertime (flock cycle plus between-flock) NH(3) emissions from this farm represented 7.8 and 8.3% of feed N as NH(3)-N, respectively, or an annual average of 8.1%.

Estrogen formation in the early rabbit embryo.

Androgen formation (3beta-hydroxysteroid dehydrogenase activity) was detectable in the rabbit blastocyst on day 5 of gestation (before implantation); estrogen formation was first detectable on day 7. The capacity to form estrogen on the day of implantation suggests that estrogen formation in the blastocyst may play a role in the implantation process.

Female feathering in sebright cocks is due to conversion of testosterone to estradiol in skin.

Sebright cocks develop a female feathering pattern but revert to normal male feathering after castration. Administration of testosterone to castrated cocks causes male comb development and reappearance of female feathering. Dihydrotes-tosterone treatment supports development of a male comb but does not induce female feathering. Since testosterone but not dihydrotestosterone is converted to estradiol in the skin of the Sebright, the female feathering appears to be the result of increased conversion of testosterone to estradiol.

Elemental composition of lunar surface material.

Elemental abundances, so far obtained, derived from the analysis of Apollo 11 lunar material are reported. Similarities and differences exist between lunar material, the eucritic achondrites, and the augite achondrite Angra dos Reis, the analysis of which is also reported.

Case of fulminant leptospirosis in a renal transplant patient.

We present a case of fulminant leptospirosis that was acquired in the suburban area by a 48-year-old male renal transplant recipient. He developed acute renal and hepatic failure with profound jaundice. Spirochetes were identified on liver biopsy. Weil's disease was suspected, and the diagnosis was further supported by a positive serum Leptospira interrogans icterohaemorrhagiae antibody titer. Unfortunately, he suffered from recurrent lower gastrointestinal bleeding, had a prolonged hospital course, and eventually succumbed to overwhelming sepsis. This case is the third report to our knowledge of leptospirosis in a renal transplant recipient in the English literature.

Design of a light stimulator for fetal and neonatal magnetoencephalography.

The design, safety analysis and performance of a fetal visual stimulation system suitable for fetal and neonatal magnetoencephalography studies are presented. The issue of fetal, neonatal and maternal safety is considered and the maximum permissible exposure is computed for the maternal skin and the adult eye. The risk for neonatal eye exposure is examined. It is demonstrated that the fetus, neonate and mother are not at risk.

The effect of sesamoid position on outcome following scarf osteotomy for hallux abducto valgus.

BACKGROUND: Hallux valgus is a common forefoot condition, with numerous operations described to correct the deformity. Debate remains as to the relative importance of correcting the position of the sesamoid apparatus. METHODS: Forty-six cases were reviewed. Preoperative and post-operative X-rays were used to measure forefoot width, inter-metatarsal angle (IM), hallux valgus (HV) angle and sesamoid position (Reynolds stations). Satisfaction was assessed via questionnaire. RESULTS: Significant improvements were seen in all radiological parameters. 37/43 patients were satisfied with the result. Comparison between the satisfied and non-satisfied group revealed significant differences in the IM angle (p<0.05) and HV angle (p<0.05). However, patient satisfaction was not associated with post-op sesamoid position or change in sesamoid position (p>0.05). CONCLUSIONS: This study showed that scarf osteotomy, can successfully correct hallux valgus, with high levels of satisfaction. Satisfaction is associated with a greater correction of deformity. Improvement in sesamoid position was not associated with patient satisfaction.

Considering the Role of Adaptive Evolution in Models of the Ocean and Climate System.

Numerical models have been highly successful in simulating global carbon and nutrient cycles in today's ocean, together with observed spatial and temporal patterns of chlorophyll and plankton biomass at the surface. With this success has come some confidence in projecting the century-scale response to continuing anthropogenic warming. There is also increasing interest in using such models to understand the role of plankton ecosystems in past oceans. However, today's marine environment is the product of billions of years of continual evolution-a process that continues today. In this paper, we address the questions of whether an assumption of species invariance is sufficient, and if not, under what circumstances current model projections might break down. To do this, we first identify the key timescales and questions asked of models. We then review how current marine ecosystem models work and what alternative approaches are available to account for evolution. We argue that for timescales of climate change overlapping with evolutionary timescales, accounting for evolution may to lead to very different projected outcomes regarding the timescales of ecosystem response and associated global biogeochemical cycling. This is particularly the case for past extinction events but may also be true in the future, depending on the eventual degree of anthropogenic disruption. The discipline of building new numerical models that incorporate evolution is also hugely beneficial in itself, as it forces us to question what we know about adaptive evolution, irrespective of its quantitative role in any specific event or environmental changes.

An objective assessment of fetal and neonatal auditory evoked responses.

OBJECTIVE: We propose to use cross-correlation function to determine significant fetal and neonatal evoked responses (ERs). METHODS: We quantify ERs by cross-correlation between the stimulus time series and the recorded brain signals. The statistical significance of the correlation is calculated by surrogate analysis. For validation of our approach we investigated a model which mimics the generation of ERs. The model assumes a fixed latency of the ER and contains two parameters, epsilon and lambda. Whether or not the system responds to a given stimulus is controlled by epsilon. The amount to which the system is excited from the base line (background activity) is governed by lambda. We demonstrate the technique by applying it to auditory evoked responses from four fetuses (21 records) between 27 and 39 weeks of gestational age and four neonates (eight records). RESULTS: The method correctly identified the ER and the latency incorporated in the model. A combined analysis of fetuses and neonates data resulted in a significant negative correlation between age and latency. CONCLUSIONS: The analysis of ER, especially for fetal and newborn recordings, should be based on advanced data analysis including the assessment of the significance of responses. The negative correlation between age and latency indicates the neurological maturation. SIGNIFICANCE: The proposed method can be used to objectively assess the ER in fetuses and neonates.

Steroid 5 alpha-reductase 2 deficiency.

In the 20 yr since it was established that impairment of dihydrotestosterone formation is the cause of a rare form of human intersex, a wealth of information has accumulated about the genetics, endocrinology, and variable phenotypic manifestations, culminating in the cloning of cDNAs encoding two 5 alpha-reductase genes and documentation that mutations in the steroid 5 alpha-reductase 2 gene are the cause of 5 alpha-reductase deficiency. Perplexing and difficult problems remain unresolved, e.g. whether the variability in manifestations is due to variable expressions of steroid 5 alpha-reductase 1 or to effects of testosterone itself. It is also imperative to establish whether defects in steroid 5 alpha-reductase 2, perhaps in the heterozygous state, are responsible for a portion of cases of sporadic hypospadias, to determine whether 5 alpha-reductase plays a role in progesterone action in women, and to elucidate the relation between androgen action and gender role behavior.

Activated B-cell immunophenotype might be associated with poor prognosis of primary central nervous system lymphomas.

Primary central nervous system (PCNS) diffuse large B-cell lymphoma (DLBCL) is an aggressive form of non-Hodgkin's lymphoma whose growth is restricted to the central nervous system and eye. Primary CNS DLBCL has a poor prognosis relative to other extranodal DLBCL. Recently DLBCL has been subclassified as germinal and non-germinal center B-cell types using microarray. Germinal center B-cell DLBCL is associated with better prognosis compared to non-germinal center B-cell group. The objective of the study was to subcategorize the PCNS DLBCL into germinal center and non-germinal center DLBCL using immunohistochemistry and to correlate its prognostic significance. 21 immunocompetent patients were diagnosed with PCNS DLBCL over last 20 years at William Beaumont Hospital. Clinical data on outcome were collected and their specimens were retrieved. Immunohistochemical staining was done using markers, CD20, CD10, Bcl-6, MUM-1, MIB-1, Bcl-2 and by molecular analysis of the immunoglobulin heavy chain gene (IgH) variable region. Immunohistochemistry showed 1/21 (positive cases/examined cases) for CD10, 19/21 for Bcl-6, 19/21 for MUM-1 and 15/21 for Bcl-2. The expression pattern of CD10(-) MUM-1(+) is corresponded to the non-germinal center DLBCL. The MIB-1 index ranged from 40--80% with a mean of 57%, indicating a high proliferation of lymphoma cells. The IgH gene variable region analysis showed monoclonality in 15 of 21 cases (71%). Primary CNS DLBCL has a non-germinal center B-cell phenotype in majority of cases and has a high Bcl-2 positivity and MIB-1 index. These features might be associated with poor prognosis.

Cushing's syndrome in a clinic population with diabetes.

BACKGROUND: A recent report has suggested that occult Cushing's syndrome (CS) may be present in a significant number of patients with type 2 diabetes mellitus. The aim of this study was to determine whether any patients in our clinic population with diabetes had this condition. METHODS: One hundred and seventy-one consecutive overweight attendees at the diabetic clinic were enrolled in a study to assess the presence of occult CS. The initial screen was with the 1 mg overnight dexamethasone suppression test and follow-up testing, where indicated was with a 24 h collection for urine-free cortisol. RESULTS: Thirty-one of 171 patients had a positive result from the overnight dexamethasone suppression test. Follow-up testing with 24 h urine-free cortisol reduced the number of patients with positive results to 3. Two of these were shown to have alcoholic pseudo-CS. The third patient has had several high urine-free cortisol results, in the presence of normal scans of pituitary and adrenals. He has no stigmata of CS and is being observed. CONCLUSION: Based on the results of our study, there would appear to be little value in screening type 2 diabetics for CS, in the absence of clinical suspicion.

Biosynthetic origin of serum cholesterol in the squirrel monkey: evidence for a contribution by the intestinal wall.

The possibility that the intestinal wall serves as a biosynthetic site for serum cholesterol has been examined in two types of studies in the squirrel monkey. First, animals were fed cholesterol in order to inhibit cholesterol synthesis in the liver, and the intestinal lymph ducts were cannulated. After the administration of acetate-2-(14)C it was possible to demonstrate that cholesterol synthesized by the intestinal wall enters intestinal lymph and thereby in the intact animal enters the circulating pool. Second, an attempt to quantitate the significance of this intestinal contribution has been made in animals fed cholesterol-3-(3)H and injected with cholesterol-4-(14)C for long periods. By an application of the technique of analysis utilizing the isotopic steady state we estimated as a minimal value that in the squirrel monkey 1.5-2.0 mg of cholesterol synthesized in the intestinal wall reaches the circulation each day.

The measurement of the exchangeable pools of cholesterol in the baboon.

Five male baboons were fed cholesterol-1alpha-(3)H until an isotopic steady state was approached in which the ratio of serum to dietary cholesterol specific activity was constant. The animals were then given single intravenous injections of cholesterol-4-(14)C, and the disappearance curves of the (14)C from the circulation were followed for 70-85 days. The total exchangeable cholesterol pools under these conditions were determined by carcass analysis at the end of the experiment and were shown to agree closely with the sums of the two exchangeable cholesterol pools as predicted from analysis of the die-away curve in terms of a two exchangeable pool model, assuming that entry into and exit from the system occur predominantly through the more rapidly exchanging of the two pools. These results have been interpreted as support for the validity of a model consisting of two exchangeable pools and one nonexchangeable or very slowly exchangeable pool as an approximation of over-all cholesterol metabolism in this species. In addition, an anatomical and chemical dissection of these pools was performed. While the three pool model is not applicable to every tissue, it has been possible to show that its general applicability in the intact animal stems from the fact that the major portions of the three cholesterol pools of the body lie within a limited number of tissues.

The relation between cholesterol absorption and cholesterol synthesis in the baboon.

To determine the relation between cholesterol absorption, total endogenous cholesterol synthesis, and hepatic cholesterol synthesis in a primate, cholesterol synthesis has been studied in biopsies of liver and ileum from normal baboons fed varying amounts of cholesterol and in biopsies of liver from baboons that had been subjected to ileal diversion. In addition, total cholesterol production rates, cholesterol absorption, and total endogenous cholesterol synthesis have been measured in these animals by a double isotope technique in which the animals were given a single injection of cholesterol-4-(14)C and fed constant amounts of cholesterol-1,2-(3)H for 4 months. From these studies, it has been concluded that on a low cholesterol intake cholesterol synthesis in the liver accounts for about three-fourths of total endogenous cholesterol production. The feeding of cholesterol produces complete inhibition of hepatic synthesis in the normal animal only when absorption approximates the amount synthesized by the liver when no cholesterol is fed, e.g., 400-500 mg/day. Finally, the intestine, which does not possess complete negative feedback control of cholesterol synthesis when cholesterol is fed, may be a significant site of nonhepatic cholesterol synthesis in these animals. In studies of four baboons subjected to ileal diversion, it was concluded that the regulation of cholesterol synthesis is distinctly different when the enterohepatic circulation is interrupted. These animals did not exhibit negative feedback of hepatic cholesterol synthesis when cholesterol was fed, despite the fact that cholesterol absorption approximated that of normal animals fed similar diets. The inference has been drawn that bile acids may be involved directly or indirectly in the regulation of hepatic cholesterol synthesis in this species or that the ileum itself may modulate the hepatic negative feedback.

Cholesterol synthesis in the squirrel monkey: relative rates of synthesis in various tissues and mechanisms of control.

Cholesterol synthesis has been extensively investigated in various tissues of lower mammals; however, there is little specific information concerning cholesterologenesis in the primate. Furthermore, experiments in whole animals suggest that important differences may exist in the features of cholesterologenesis in the dog and rat versus the monkey and man. Using the new world squirrel monkey, therefore, we performed the present studies to determine the rates of cholesterologenesis in various tissues per unit weight, to define the relative rates of whole organ synthesis, and to evaluate the operation of control mechanisms in these tissues.In control animals fed a low cholesterol chow diet, the liver and ileum were the two most active sites for cholesterologenesis followed, in order, by the colon, esophagus, and proximal small bowel. Rates of synthesis in 10 other tissues tested were considerably lower than these found in the gastrointestinal tract. When rates of whole organ synthesis were calculated, three tissues, i.e., liver, bowel, and skin, accounted for 92% of the total demonstrable synthetic activity.Following cholesterol feeding utilizing either a solid chow or liquid formula diet, marked suppression of hepatic cholesterologenesis occurred while synthesis in other organs remained essentially unaltered. Similarly, fasting animals for periods up to 96 hr resulted in suppression of synthesis in the liver, but not in various levels of the intestine. Finally, biliary diversion for 48 hr caused a twofold increase in hepatic cholesterologenesis and a six- to eightfold increase in sterol synthesis in the small but not the large intestine.