Impact of PSMA-targeted imaging with 18F-DCFPyL-PET/CT on clinical management of patients (pts) with biochemically recurrent (BCR) prostate cancer (PCa): Results from a phase III, prospective, multicenter study (CONDOR)

5501

Background: Current imaging modalities are inadequate for localizing and characterizing occult disease in men with BCR PCa, particularly in pts with low PSAs (<2 ng/mL). There is a need for improved diagnostic imaging to better inform treatment planning. 18F-DCFPyL (PyL) is a novel PET imaging agent that binds selectively with high affinity to PSMA, which is overexpressed in PCa cells. Methods: Men ≥18 years- with rising PSA after definitive therapy and negative or equivocal standard of care imaging (e.g., CT/MRI, bone scintigraphy) were enrolled. A single 9 mCi (333 MBq) ± 20% dose of PyL was injected, followed by PET/CT 1-2 hours later. Primary endpoint was correct localization rate (CLR), defined as percentage of pts with a 1:1 correspondence between at least one lesion identified by PyL-PET/CT and the composite standard of truth: pathology, correlative imaging, or PSA response. The trial was successful if the lower bound of the 95% confidence interval (LLCI) for CLR exceeded 20% for two of three independent, blinded central PyL-PET/CT reviewers. The secondary endpoint, impact of PyL-PET/CT on clinical management of pts was based on the treating physician’s documented clinical plans before and after PyL-PET/CT. Results: 208 men (median PSA 0.8 [0.2 - 98.4] ng/mL) underwent PyL PET/CT. The study achieved its primary endpoint: CLR of 84.8% to 87.0% among the three PyL-PET/CT readers; the LLCI for CLR by all three reviewers was >77%. Here we report the clinical impact. Based on local radiology assessment, PSMA-avid lesion(s) were identified in 69.3% (142/208) of pts. 63.9% (131/205) had a change in intended management after PyL-PET/CT, of which 78.6% (103/131) were attributable to positive PyL finding(s) and 21.4% (28/131) to negative PyL scans. Changes included: salvage local therapy to systemic therapy (n=58); observation before initiating therapy (n=49); noncurative systemic therapy to salvage local therapy (n=43); and planned treatment to observation (n=9). PyL was well tolerated with one drug-related SAE (hypersensitivity) and the most common AE being headache (n=4; 1.9%). Conclusions: PSMA-targeted PyL-PET/CT detected and localized occult disease in most men with BCR presenting with negative or equivocal conventional imaging. PyL-PET/CT led to changed management plans in the majority of pts, thus providing evidence that clinicians find PSMA PET imaging useful in men with recurrent or suspected metastatic PCa. Clinical trial information: NCT03739684 .

Long-term survival and safety from a multi-center, open-label, pivotal phase 2 study of iobenguane I 131 in patients (Pts) with unresectable, locally advanced or metastatic pheochromocytoma or paraganglioma (PPGL)

4108

Background: PPGL, rare neuroendocrine tumors with a 5-yr survival rate as low as 12%, have a high unmet need for effective treatment options. AZEDRA, a high-specific-activity iodine-131 meta-iodobenzylguanidine (HSA I-131-MIBG), is the first and only FDA- approved therapeutic radiopharmaceutical agent indicated for the treatment of adult and pediatric pts with iobenguane scan positive, unresectable, locally advanced or metastatic PPGL who require systemic anticancer therapy. Methods: Pts with advanced disease who were heavily pre-treated and were ineligible for curative surgery or chemotherapy received a dosimetric dose followed by up to two therapeutic doses (each at 296 MBq/kg to a max of 18.5 GBq). The primary endpoint, defined as the proportion of pts with at least 50% reduction of all antihypertensive medication(s) lasting ≥6 months, was met and previously reported. Updated secondary endpoints including overall survival (OS) and safety are reported. Results: A dosimetric dose of HSA I-131-MIBG was administered to 74 pts. Of those, 68 pts received one therapeutic dose and 50 received two doses of HSA I-131-MIBG. Clinical benefit rates (objective tumor responses defined by RECIST 1.0 and stable disease) were observed in 71.4% and 98.0% of pts receiving one and two therapeutic doses, respectively. As of Jan 25, 2019, median OS for all pts was 41.1 months (95% CI 31.1, 91.2). Median OS was 17.5 months (95% CI 4.0, 31.5) and 48.7 months (95% CI 33.2, 91.2) in pts receiving one and two doses, respectively. A tail of survival was observed, with OS of 73.1% at 2 yrs and 44.2% at 4 yrs. The most common (≥50%) adverse events were nausea, fatigue, and myelosuppression. Myelosuppressive events resolved within 4-8 wks without requiring stem cell transplantation. Late radiation toxicity included 8 pts with secondary malignancies (myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), colon cancer, and lung carcinoma) of which MDS, ALL and AML were considered related to I-131 radiotherapy. Conclusions: Updated results from this pivotal phase 2 study suggest that HSA I-131-MIBG is an efficacious and safe treatment for advanced PPGL. Clinical trial information: NCT00874614.

Diagnostic performance of 18F-DCFPyL in the OSPREY Trial: A prospective phase 2/3 multicenter study of 18F-DCFPyL PET/CT imaging in patients (Pts) with known or suspected metastatic prostate cancer (mPC)

5012

Background: Accurate detection of prostate cancer is imperative to patient management, yet standard imaging methods perform poorly in accurately detecting mPC. 18F-DCFPyL is a novel PET imaging agent that selectively binds to prostate-specific membrane antigen, a recognized target for prostate cancer. OSPREY was a prospective, multicenter study in pts with either newly diagnosed high-risk prostate cancer (cohort A), or known or suspected mPC (cohort B). Here we focus on Cohort B. Methods: 117 men planned for biopsy of recurrent or mPC received 18F-DCFPyL. Pts underwent image-guided biopsy. Sensitivity, positive predictive value (PPV), and safety of 18F-DCFPyL PET/CT were the key endpoints for Cohort B. 18F-DCFPyL PET/CT scans were evaluated by three independent, blinded central readers; and results were compared to histopathology as the truth standard. Results: The sensitivity and PPV of 18F-DCFPyL PET/CT as compared to histopathology ranged from 92.9-98.6% (lower bound of 95% CI: 84.0-91.6%) and 81.2-87.8%, respectively. Diagnostic performance by anatomic location showed high sensitivity and high PPV in all sites of disease (Table). Only two (1.7%) cohort B pts experienced ≥1 drug-related AE (dysgeusia and generalized rash), both were mild (Grade 1) in severity. Conclusions: 18F-DCFPyL PET/CT was well tolerated and demonstrated high sensitivity and PPV in accurately detecting nodal, bone, and visceral/soft tissue metastases. A positive 18F-DCFPyL PET/CT scan is highly likely to represent pathologically proven distant disease, demonstrating the potential of 18F-DCFPyL as a PET imaging agent to favorably influence treatment planning. Clinical trial information: NCT02981368. [Table: see text]

A phase III, multicenter study to assess the diagnostic performance and clinical impact of 18F-DCFPyL PET/CT in men with suspected recurrence of prostate cancer (CONDOR)

TPS5093

Background: Early and accurate detection of recurrent or metastatic prostate cancer remains an unmet diagnostic need for patient management. While agents for positron emission tomography (PET), such as 11C-choline and 18F-fluciclovine, have emerged as options for imaging recurrent prostate cancer, these agents are not specific for the disease. 18F-DCFPyL is a novel, low-molecular weight, PET radiopharmaceutical that binds selectively to prostate-specific membrane antigen with high affinity. In prior studies, 18F-DCFPyL PET/CT has shown reliable diagnostic performance in detecting metastatic or recurrent prostate cancer (Rowe Mol Imaging Biol 2016 18:411-19; Gorin J Urol 2018 1999:126-32). Methods: CONDOR is a phase 3, multicenter, open-label study designed to assess the diagnostic performance and clinical impact of 18F-DCFPyL PET/CT in men with suspected recurrent or metastatic prostate cancer. Approximately 200 patients are planned to be enrolled across 15 centers in the United States and Canada. Eligible patients ≥18 years of age must have histologically confirmed prostate adenocarcinoma, have rising PSA after definitive therapy, and negative or equivocal conventional imaging. A single 9 mCi (333 MBq) dose of 18F-DCFPyL is administered, followed by whole body PET/CT scan 1 hour later. The primary objective is to assess the correct localization rate (percentage of patients with a one-to-one correspondence between localization of at least one lesion identified on 18F-DCFPyL PET/CT and the composite truth standard, defined as either evaluable histopathology, informative correlative imaging, or PSA response after radiation therapy). Additional study objectives include safety and tolerability of 18F-DCFPyL, impact on intended treatment plans, detection rates and PPV of 18F-DCFPyL by region, and detection rates by baseline PSA. 18F-DCFPyL PET/CT results are centrally reviewed by independent readers blinded to all clinical and other imaging information. As of February 9, 2019, a total of 36 patients have been dosed in the study. Clinical trial information: NCT03739684.

Pooled safety analysis of high-specific-activity I-131 MIBG in iobenguane scan positive cancer patients

388

Background: Iobenguane scan positive cancers include pheochromocytoma and paraganglioma (PPGL), neuroblastoma, and gastroenteropancreatic neuroendocrine tumors. A pooled analysis was conducted to assess the safety profile of high-specific-activity I-131 metaiodobenzylguanidine (HSA I-131 MIBG [AZEDRA]) in PPGL and neuroblastoma. Methods: Safety data were pooled from four clinical studies with 118 subjects who received HSA I-131 MIBG. Adverse events (AEs) were described by age, gender, race, number of HSA I-131 MIBG doses, temporal association of AEs within 12 weeks after therapeutic dose 1, vital signs, laboratory values, hematological events of Grade 3/4 or serious AEs, and changes in mean hematology values over a period of 12 months. Results: Out of 118 subjects, mean age was 47.0 ± 18.9 years (range 3-76); 57.6% were males and 74.6% were white. A total of 102 (86.4%) subjects had at least one AE assessed as treatment-related. The incidences of most AEs were similar among both genders and all racial groups. The most common toxicities associated with HSA I-131 MIBG were gastrointestinal disorders, with nausea the most prevalent. The incidences of nausea and salivary gland pain showed decreasing trends with age while dyspnea, asthenia, and peripheral edema showed increasing trends. The second most common toxicities were hematologic. Following each therapeutic dose, mean hemoglobin, leukocytes, neutrophils, and platelets decreased. Most hematological AEs resolved within 12 weeks, and recovery to pre-therapeutic dose values was apparent 6 months after each therapeutic dose. After therapeutic dose 1, higher percentages of subjects experienced AEs in the first 2 weeks, and the incidence decreased beyond 6 weeks. No notable changes were observed in clinical chemistry tests. The incidence of Grade 3/4 AEs was similar following each therapeutic dose. Conclusions: HSA I-131 MIBG was safe and well-tolerated among subjects with iobenguane scan positive cancers. No trends were discerned between baseline characteristics and AEs. Hematology results reflected toxicity profile expected in a population of subjects administered a radiopharmaceutical. Clinical trial information: Pooled Safety.

Should Europe follow the US and declare obesity a disease?: a discussion of the so-called utilitarian argument

In 2013, the American Medical Association (AMA) decided to recognize obesity as a disease. One of the main arguments presented in favor of this was broadly 'utilitarian': the disease label would, it was claimed, provide more benefits than harms and thereby serve the general good. Several individuals and groups have argued that this reasoning is just as powerful in the European context. Drawing mainly on a review of relevant social science research, we discuss the validity of this argument. Our conclusion is that in a Western European welfare state, defining obesity as a disease will not on balance serve the general good, and that it is therefore more appropriate to continue to treat obesity as a risk factor. The main reasons presented in favor of this conclusion are: It is debatable whether a disease label would lead to better access to care and preventive measures and provide better legal protection in Europe. Medicalization and overtreatment are possible negative effects of a disease label. There is no evidence to support the claim that declaring obesity a disease would reduce discrimination or stigmatization. In fact, the contrary is more likely, since a disease label would categorically define the obese body as deviant.

PIK3CA mutations, PTEN, and pHER2 expression and impact on outcome in HER2-positive early-stage breast cancer patients treated with adjuvant chemotherapy and trastuzumab

BACKGROUND

This study was conducted to determine the frequency of PIK3CA mutations and human epidermal growth factor receptor-2 (HER2) phosphorylation status (pHER2-Tyr1221/1222) and if PIK3CA, phosphatase and tensin homolog (PTEN), or pHER2 has an impact on outcome in HER2-positive early-stage breast cancer patients treated with adjuvant chemotherapy and trastuzumab.

PATIENTS AND METHODS

Two hundred and forty HER2-positive early-stage breast cancer patients receiving adjuvant treatment (cyclophosphamide 600 mg/m2, epirubicin 60 mg/m2, and fluorouracil 600 mg/m2) before administration of 1 year trastuzumab were assessable. PTEN and pHER2 expression were assessed by immunohistochemistry. PIK3CA mutations (exons 9 and 20) were determined by pyrosequencing.

RESULTS

Five-year overall survival (OS) and invasive disease-free survival were 87.8% and 81.0%, respectively. Twenty-six percent of patients had a PIK3CA mutation, 24% were PTEN low, 45% pHER2 high, and 47% patients had increased PI3K pathway activation (PTEN low and/or PIK3CA mutation). No significant correlations were observed between the clinicopathological variables and PIK3CA, PTEN, and pHER2 status. In both univariate and multivariate analyses, patients with PIK3CA mutations or high PI3K pathway activity had a significant worse OS [multivariate: hazard ratio (HR) 2.14, 95% confidence interval (CI) 1.01-4.51, P=0.046; and HR 2.35, 95% CI 1.10-5.04, P=0.03].

CONCLUSION

Patients with PIK3CA mutations or increased PI3K pathway activity had a significantly poorer survival despite adequate treatment with adjuvant chemotherapy and trastuzumab.

TRI12 based quantitative real-time PCR assays reveal the distribution of trichothecene genotypes of F. graminearum and F. culmorum isolates in Danish small grain cereals

Quantitative real-time PCR assays, based on polymorphisms in the TRI12 gene of the trichothecene pathway, were developed to identify and quantify the trichothecene genotypes producing 3-acetyl-deoxynivalenol (3ADON), 15-acetyl-deoxynivalenol (15ADON) or nivalenol (NIV) in the Fusarium graminearum species complex, Fusarium culmorum, Fusarium cerealis and Fusarium pseudograminearum. These assays were applied on a total of 378 field samples of cereal grain of wheat, barley, triticale, rye and oats collected from 2003 to 2007 to study the trichothecene genotype composition in Danish cereals. The three genotypes, 3ADON, 15ADON and NIV were found in all five cereal species, great annual variation in the occurrence of the trichothecene genotypes was evident with considerable variation between the samples. 3ADON was the dominant genotype in barley, triticale, rye and oats while 15ADON was most dominant in wheat. The NIV genotype was found at low levels in most samples. Study of genotype composition within the Danish F. graminearum and F. culmorum population was based on principal component analysis (PCA). PCA revealed that the dominating genotype of F. graminearum in wheat is 15ADON. For barley, the PCA analysis indicated that the F. graminearum population consisted of all three genotypes, and in triticale, the F. graminearum population consisted mainly of 15ADON genotype. F. culmorum/F. cerealis showed correlation to the NIV genotype in wheat and triticale but not in barley. F. culmorum/F. cerealis also showed some correlation to 3ADON especially in wheat and triticale. Selected wheat and barley samples from 1957 to 2000 showed low amounts of F. graminearum and F. culmorum in general but with a dominance of the 3ADON genotype. 15ADON was not detected in these samples, except for very low amounts in the sample representing the years from 1997 to 2000. Detection of low amounts of the 15ADON genotype in these historical samples and the relatively high amounts of 15ADON genotype in 2003 and following years correspond well with the occurrence of F. graminearum and indicates that the 15ADON genotype was introduced along with F. graminearum around 2000. The amounts of the 3ADON and 15ADON genotypes correlated well with the total amount of DON whereas the amounts of NIV genotype correlated well with the amount of NIV in wheat and triticale but not in barley where the results indicate that Fusarium poae may also contribute to the NIV content.

Fusarium head blight of cereals in Denmark: species complex and related mycotoxins

Quantitative real-time polymerase chain reaction differentiating 10 Fusarium spp. and Microdochium nivale or M. majus was applied to a total of 396 grain samples of wheat, barley, triticale, oat, and rye sampled across Denmark from 2003 to 2007, along with selected samples of wheat and barley from 1957 to 2000, to determine incidence and abundance of individual Fusarium spp. The mycotoxins deoxynivalenol (DON), nivalenol, zearalenone, T-2, and HT-2 were quantified using liquid chromatography-double mass spectrometry. Major differences in the Fusarium species complex among the five cereals as well as great yearly variation were seen. Fusarium graminearum, F. culmorum, and F. avenaceum were dominant in wheat, with DON as the dominant mycotoxin. F. langsethiae, F. culmorum, and F. avenaceum were dominant in barley and oat, leading to relatively high levels of the mycotoxins T-2 and HT-2. F. graminearum, F. culmorum, and F. avenaceum dominated in triticale and rye. The nontoxigenic M. nivale/majus were present in significant amounts in all cereal species. Wheat and barley samples from 1957 to 1996 exhibited no or very low amounts of F. graminearum, indicating a recent increase of this pathogen. Biomass and mycotoxin data exhibited good correlations between Fusarium spp. and their corresponding mycotoxins under field conditions.

Targeted resequencing of a genomic region influencing tameness and aggression reveals multiple signals of positive selection

The identification of the causative genetic variants in quantitative trait loci (QTL) influencing phenotypic traits is challenging, especially in crosses between outbred strains. We have previously identified several QTL influencing tameness and aggression in a cross between two lines of wild-derived, outbred rats (Rattus norvegicus) selected for their behavior towards humans. Here, we use targeted sequence capture and massively parallel sequencing of all genes in the strongest QTL in the founder animals of the cross. We identify many novel sequence variants, several of which are potentially functionally relevant. The QTL contains several regions where either the tame or the aggressive founders contain no sequence variation, and two regions where alternative haplotypes are fixed between the founders. A re-analysis of the QTL signal showed that the causative site is likely to be fixed among the tame founder animals, but that several causative alleles may segregate among the aggressive founder animals. Using a formal test for the detection of positive selection, we find 10 putative positively selected regions, some of which are close to genes known to influence behavior. Together, these results show that the QTL is probably not caused by a single selected site, but may instead represent the joint effects of several sites that were targets of polygenic selection.

A North American perspective on dermoscopy: benefits, limitations, and grey zones

Dermoscopy offers novel and cost-effective diagnostic information to guide patient care for melanocytic and non-melanocytic dermatoses. This article reviews the current use of dermoscopy, including its clinical benefits and limitations. Surveys of U.S. and Canadian dermatology residents have demonstrated a desire for improved dermoscopy teaching; an abundance of evidence calls for increasing its use in the clinical setting. Using the current evidence framework, North American dermatology training centers and professional societies should work to foster dermoscopy training and use by both dermatologists and other health care providers.

Progress and prospects in mapping recent selection in the genome

One of the central goals of evolutionary biology is to understand the genetic basis of adaptive evolution. The availability of nearly complete genome sequences from a variety of organisms has facilitated the collection of data on naturally occurring genetic variation on the scale of hundreds of loci to whole genomes. Such data have changed the focus of molecular population genetics from making inferences about adaptive evolution at single loci to identifying which loci, out of hundreds to thousands, have been recent targets of natural selection. A major challenge in this effort is distinguishing the effects of selection from those of the demographic history of populations. Here we review some current progress and remaining challenges in the field.

Comparison of predilution hemodiafiltration and low-flux hemodialysis at temperature-controlled conditions using high calcium-ion concentration in the replacement and dialysis fluid

BACKGROUND

It is the prevailing view that convective dialysis techniques stabilize blood pressure. The aim of this study was to compare the hemodynamics of high-dose predilution hemodiafiltration (HDF) and low-flux hemodialysis (HD), under matched conditions and using high calcium-ion concentration in the replacement/dialysis fluid.

METHODS

13 stable hemodialysis patients were investigated in a randomized crossover, blinded controlled trial. The patients were allocated to one session of predilution HDF (substitution fluid 1.20 1/kg BW) and one session of HD at 4.5 hours. At the start of the dialysis the patient's core temperature was "locked" by an automatic feedback system regulating the dialysate temperature, thereby patient's temperature was kept stable throughout the whole treatment. The Ca ion concentration in the substitution/dialysis fluid was 1.75 mM. Cardiac output was measured hourly by the ultrasound velocity dilution method.

RESULTS

Within treatments comparisons revealed that both treatments displayed stable mean blood pressure and equally reduced cardiac output. HDF showed decreased stroke volume and increased total peripheral resistance. The pulse rate decreased significantly only during HD. Arterial temperature was kept constant during both treatments. Ultrafiltration volume, cardiopulmonary recirculation, relative blood volume, Kt/V and total energy transfer were matched for HD and HDF. The overall between treatments comparisons revealed no significant differences.

CONCLUSIONS

We have shown that during matched conditions and high calcium concentrations, the hemodynamic profiles of high dose predilution HDF and lowflux HD were similar. Both modalities showed stable mean blood pressure profiles. An acute circulatory benefit of convective solute removal over diffusive, could not be demonstrated.

Cytopathologic evaluation of lung carcinomas presenting as brain metastasis

Brain metastasis is an uncommon initial presentation of lung carcinoma. One arm of this analysis is a retrospective review of 137 cases of surgically diagnosed solitary brain metastasis, which were eventually found to be of lung origin, encountered at Hines VA Hospital during the period 1958 to 1996. The second arm is composed of fine-needle aspiration biopsy specimens of primary lung tumor in 23 patients with an initial clinical diagnosis of brain metastasis and without the benefit of surgery, seen from 1981 through 1996. Our results in both analyses indicate that pulmonary adenocarcinoma is the predominant primary tumor that initially manifests as a brain metastasis, approaching 76% (107 and 17 cases, respectively), followed by small-cell carcinoma at 20% (24 and five cases, respectively) and large-cell undifferentiated carcinoma and squamous-cell carcinoma at 2% each. The predominance of adenocarcinoma as a source of brain metastasis in lung cancer patients probably reflects its rising incidence overall of late. Collateral findings also suggest that surgical resection of a solitary and small brain metastasis as well as of a discrete lung primary, whenever feasible, as the most effective procedure to improve survival and quality of life of patients.

Adenocarcinoma of the lung: electron microscopy of fine-needle aspiration biopsy specimens--a review of 73 cases

During a 10-yr period, 128 consecutive cases of pulmonary adenocarcinoma of varying differentiation were diagnosed with percutaneous fine-needle aspiration biopsy. Sediments from the needle and syringe washings with 3% glutaraldehyde were obtained and processed for electron microscopic evaluation in 73 cases. Our results showed three types of adenocarcinoma: 62 cases of nonciliated bronchiolar cell origin, 6 cases of bronchioloalveolar cell origin, and 3 cases of mucous cell origin. In addition, there was an example of combined adenosquamous carcinoma and an instance of amphicrine carcinoma. Our study provided a more precise definition of the cytologic diagnosis and insight into the heterogeneity of lung adenocarcinoma. However, prognostic differences between cell types of lung adenocarcinoma were not observed.

[The auto- and endocrine function of the adipose tissue. Significance for metabolic complications in obesity]

The present review discusses recent research showing adipose tissue to be highly metabolically active, producing and releasing many different bioactive compounds besides free fatty acids (FFA) such as tumor necrosis factor alpha (TNF alpha), leptin, acetylation stimulating protein (ASP), plasminogen activator inhibitor-1 (PAI-1), cholesterol ester transfer protein (CETP), prostaglandins and oestrogens. Most of these compounds have autocrine effects on the adipose cells and they are presumably involved in the physiological regulation of blood flow, growth and metabolism of the adipose tissue. When the adipose tissue becomes enlarged, as seen in association with obesity, it has now been shown that several of the compounds produced in the adipose tissue (TNF, PAI-1, CETP etc.) may be directly involved in the pathogenesis of some of the complications commonly seen in association with obesity such as insulin resistance, hypertension, enhanced thrombogenesis, and premature atherosclerosis.

Metastasis of unknown origin: the role of fine-needle aspiration cytology

Metastasis of unknown origin (MUO) manifests either as a tumor deposit in an organ, often cervical lymphadenopathy, or as a multiorgan carcinomatosis. As a diagnostic and therapeutic challenge, the definition of its cell type and possibly its origin is imperative, although a limited diagnostic investigation is usually recommended. At Hines VA Hospital from 1986 to 1994, there were 116 cases with admitting clinical diagnosis of MUO, evaluated by fine-needle aspiration cytology (FNAC). The ages of patients ranged from 29 to 82 years (mean 56 years). All were male; Caucasians predominated. The FNAC examination with Diff-Quik and Papanicolaou smears were complemented with special and immunostains in 48 cases (41%) and electron microscopy in 93 cases (80%). The FNAC involved lymph nodes in 57 cases (49%), liver in 27 cases (23%), skin in 22 cases (19%), bone in six cases (5%), lung in three cases (3%), and pleura in one case (1%). The neoplasm was generally cell typed, and there were 60 adenocarcinomas/poorly differentiated carcinomas, 26 small-cell carcinomas (SCC), 23 squamous-cell carcinomas (SQCC), and six undifferentiated large-cell carcinomas. The primary source was defined in 30 cases (26%), consisting of lung in 11 cases, prostate in nine, kidney in four, colon in four, pleura in one, and peritoneum in one. Clinical correlation also supported a lung origin for the SCC, while the majority of the SQCC in upper and middle cervical lymph nodes were considered head-and-neck tumors. Our results affirm that FNAC is a viable and simple procedure in MUO investigations.

Pleural effusion cytology of embryonal rhabdomyosarcoma

This case report concerns an embryonal rhabdomyosarcoma of the testis in a 31-yr-old white male patient who underwent radical left orchiectomy, followed by combined irradiation and chemotherapy, and who 2 yr later presented with dyspnea at rest, nonproductive cough, and lower back pain for 1 wk. Chest radiographs demonstrated a bilateral pleural effusion and diffuse infiltrating lesion of the pleurae, mimicking a mesothelioma. The pleural fluid displayed noncohesive, malignant, small, round cells about 2-5 times larger than mature lymphocytes. They had large, darkly stained, pleomorphic nuclei and bubbly cytoplasm with poorly defined borders. The diagnosis of embryonal rhabdomyosarcoma was supported by a positive myosin immunostaining and ultrastructural findings of intracytoplasmic actin and myosin-type microfilaments. Our case is also notable in that the tumor was a pure rhabdomyosarcoma involving a testicular origin, and the patient is the oldest reported in the literature.

Comparison of dose requirement, serum erythropoietin and blood pressure following intravenous and subcutaneous erythropoietin treatment of dialysis patients. IV and SC erythropoietin

OBJECTIVE

The purpose of the study was to investigate the effect of route of administration of erythropoietin (EPO) on the dose requirement in dialysis patients after intravenous (IV) and subcutaneous (SC) therapy.

METHODS

The study was performed as a single centre, prospective, open, combined parallel and cross-over study of 50 dialysis patients, consecutively randomised to IV or SC treatment with EPO. The initial dose was 49 U.kg-1 3-times weekly, adjusted to increase haemoglobin (Hgb) from a median 5.3 mmol.1(-1) to a target of haemoglobin 6.5-7.5 mmol.1(-1). After reaching the target level, the haemoglobin was maintained for 4 months (Period 1). Then IV and SC treatment was switched for a further 4 months (Period 2). The study included high risk patients. The adjustment period was completed by 38 patients, Period one by 32 patients (IV/SC = 15/17; male/female = 19/13; age = 54 (24- 71) y), and Period two by 22 patients.

RESULTS

No significant difference was found between the two groups in the reticulocyte response, the rate of Hgb increase (IV 0.7 versus SC 0.5, mmol.1(-1). month-1), time to reach target level (IV 43 versus SC 60 days), or total EPO dose per increase in haemoglobin to target level (IV 663 versus SC 946 (U.kg-1) per (mmol Hgb.1(-1)). The overall median maintenance dose during the last month of the two four month periods was 105 (range IV 51-336) U.kg-1.w-1 and SC 104 (range 21-321) U.kg-1.w-1. Through serum EPO levels were significantly higher during SC treatment. The blood pressure did not change significantly from the base level after either route of administration; start 133/80 versus 143/80 mmHg, target 127/78 versus 154/85 mmHg, and maintenance period 140/84 versus 142/85 mmHg. Thus, three-times weekly IV or SC EPO did not differ significantly in efficacy or in the effect on blood pressure in dialysis patients.

Pharmacokinetic interaction between cyclosporine and the dihydropyridine calcium antagonist felodipine

OBJECTIVE

In a double blind, randomised, placebo-controlled, cross-over study 12 healthy male volunteers were allocated to receive felodipine + placebo, cyclosporine + placebo, and felodipine + cyclosporine in order to investigate the interaction between the calcium channel blocker felodipine and cyclosporine as it affects the pharmacokinetics of felodipine, dehydrofelodipine, and cyclosporine, and 24-hour blood pressure measurements.

METHODS

Single doses of cyclosporine (capsules, 5 mg/kg body weight) and of felodipine (extended release (ER) tablets 10 mg) were given at a 1-2 week interval. Plasma drug concentrations were followed for 2 days after drug intake.

RESULTS

For cyclosporine, Cmax was increased after combined treatment (16%) compared to cyclosporine alone, but felodipine did not influence other kinetic parameters of cyclosporine. For felodipine, combined treatment with cyclosporine and felodipine increased AUC and Cmax (58% and 151%, respectively) and lowered mean residence time (24%) significantly compared to felodipine alone. For the metabolite dehydrofelodipine, too, AUC and Cmax were increased after the combined treatment (43% and 94%, respectively). Mean 24-hour systolic and diastolic blood pressures were significantly lower after felodipine, both when felodipine was given alone (121/68 mmHg) and in combination with cyclosporine (122/68 mmHg) compared to cyclosporine alone (127/73 mmHg).

CONCLUSION

A combined single dose of cyclosporine and felodipine in healthy subjects increased the AUC and Cmax of felodipine suggesting a cyclosporine-induced decrease in the first-pass metabolism of felodipine, whereas the AUC of cyclosporine was only slightly increased by felodipine.

Effects of high dose atrial natriuretic peptide on renal haemodynamics, sodium handling and hormones in cirrhotic patients with and without ascites

To elucidate and to try to reverse the antinatriuretic mechanisms in liver cirrhosis, atrial natriuretic peptide (ANP) was given as a pharmacological bolus dose (2 micrograms per kg body weight) to 14 cirrhotic patients, and as a control to 14 healthy subjects. The nine patients with ascites had baseline values of glomerular filtration rate (GFR), effective renal plasma flow (ERPF) and blood pressure (BP) similar to controls. Their distal tubular fractional reabsorption of sodium (DFRNa), estimated by the lithium clearance technique, was higher than in controls, and so were plasma values of aldosterone (564 vs. 119 pmol l-1 medians), endothelin (1.23 vs. 0.63 pmol l-1), ANP (7.5 vs. 3.6 pmol l-1) and cyclic GMP (8.8 vs. 4.6 nmol l-1); p < 0.01 for all. The five patients without ascites had higher GFR and ERPF, and lower plasma angiotensin II than controls. After ANP injection, similar plasma levels of ANP and cyclic GMP were reached in all groups. Urinary sodium excretion rate increased in controls (0.23 to 0.52 mmol min-1, p < 0.01), while GFR increased (108 to 117 ml min-1, p < 0.05), and DFRNa decreased (93 to 89%, p < 0.01). In cirrhotics with ascites sodium excretion was unaltered (0.12 to 0.11 mmol min-1), and so was GFR (84 to 83 ml min-1). Proximal tubular fractional reabsorption of sodium increased after 90 min, whereas DFRNa decreased immediately (97 to 96%, p < 0.01) though less markedly than in controls. Sodium excretion increased in four of five patients without ascites (0.23 to 0.27 mmol min-1, medians). In patients with ascites, endothelin in plasma decreased after ANP (p < 0.05). Plasma levels of angiotensin II, aldosterone and vasopressin were unchanged in all groups. In conclusion, although hyper-reabsorption of sodium occurred in the distal rather than the proximal part of the nephron in cirrhotic patients with ascites, ANP had no natriuretic effect. This was most probably due primarily to the lack of increase of GFR and blunted inhibition of DFRNa, attributed to high aldosterone. The effect of ANP in suppressing the high endothelin did not seem to improve sodium excretion.

Porphyria in childhood

Porphyria in childhood is an uncommon problem but the recognition of these disorders is vitally important for affected children. Of the cutaneous porphyrias, erythropoietic protoporphyria, congenital erythropoietic porphyria, hepatoerythropoietic porphyria, and the hereditary form of porphyria cutanea tarda (PCT) can present in infancy or childhood. This article focuses on the porphyrias that present in infants and children along with a brief discussion of pathogenesis, cutaneous histopathology, and genetics of these metabolic disorders.

The metabolism of erythropoietin in liver cirrhosis patients compared with healthy volunteers

The purpose of the investigation was to study the metabolism of erythropoietin (EPO) in patients with liver disease. Twelve patients with liver cirrhosis and 10 healthy volunteers were studied. The patients were moderately anemic with a hematocrit of 33 vs 42% (medians) in the volunteers. The pharmacokinetic parameters were calculated after an intravenous (i.v.) injection of 100 U/kg of recombinant human EPO. The serum EPO was measured by radioimmunoassay at regular intervals until 48 h. The median terminal elimination half life in the cirrhosis patients was 5.15 h vs 5.37 h in the control subjects. The clearance was 7.78 vs 7.52 ml/min/1.73 m2 (ns). The steady-state volume of distribution was 3.69 vs 3.09 1/1.73 m2 (ns). The estimated endogenous EPO production was significantly higher in liver cirrhosis (486 vs 290 U/d/1.73m2, p < 0.01). The basal serum EPO was significantly higher in the cirrhosis patients (43.5 vs 26.3 U/l, p < 0.01). The hematocrit correlated inversely with the basal serum EPO level in the cirrhosis patients (r = -0.63, p < 0.04). The EPO-clearance was not related to the presence of ascites, esophageal varices, or to abnormal blood chemistry. It was concluded that normal metabolism of EPO was maintained in liver cirrhosis and that the cirrhotic patients had a moderate compensatory increase of EPO production in response to anemia.

Reduced production, absorption, and elimination of erythropoietin in uremia compared with healthy volunteers

The purpose of this study was to investigate the metabolism of erythropoietin (EPO) in uremia compared with healthy subjects. Twenty-one patients (nine men and 12 women) with end-stage renal failure and anemia and 12 healthy volunteers (3 women and nine men) were studied. The pharmacokinetic parameters were calculated after an i.v. and a femoral sc injection of 100 U/kg of recombinant human EPO. The serum EPO (s-EPO) was measured by radio-immunoassay at regular intervals until 48 h (i.v.) and 120 h (sc). In uremia, the median terminal elimination half-life was significantly longer (8.31 versus 4.92 h; P < 0.001) and the clearance was reduced (5.00 versus 7.88 mL/min per 1.73 m2; P < 0.01). The volume of distribution was (3.70 versus 3.31 L/1.73 m2) not significant. The estimated endogenous EPO production was significantly lower in uremia (146 versus 290 U/day per 1.73 m2; P < 0.001). After sc administration, the bioavailability was significantly lower in the patients (23.7 versus 38.5%; P < 0.01), and the maximal s-EPO was lower (113 versus 153 U/L; P < 0.05) and delayed (15.4 versus 11.0 h; P < 0.02), but the mean input time (sc) was not significantly different (23.3 versus 27.8 h). The basal s-EPO was lower in the uremic patients (20.0 versus 26.3 U/L; P < 0.05). There was no difference between patients treated with hemodialysis and peritoneal dialysis or between uremic men and women. There was no correlation between the pharmacokinetic parameters and age.(ABSTRACT TRUNCATED AT 250 WORDS)

The pharmacokinetics of recombinant human erythropoietin after subcutaneous injection at different sites

The pharmacokinetics of recombinant human erythropoietin (RhEPO) were investigated after subcutaneous (s.c.) injection in the thigh and in the abdominal wall. Eleven healthy subjects, age 24.4 years (median), were studied. Each subject received two s.c. injections of 100 U.kg-1 RhEPO dissolved in 1 ml water: one injection in the thigh and another in the abdomen. Serum erythropoietin was measured regularly by radioimmunoassay until 144 h after each injection. The mean residence time was significantly longer after injection in the thigh than in the abdomen (32.7 vs 26.2 h). The estimated half-life of absorption was significantly longer after injection in the thigh than after abdominal application (14.9 vs 12.3 h). The estimated half-life of elimination was not significantly different (4.4 vs 4.8 h). The relative difference in the area under the curve between injection in the abdomen and the thigh in the same subject ranged from -36% to +68% but there was no significant difference in bioavailability. The peak concentration was not significantly different and appeared at around 10 h (Cmax thigh, 175 U.l-1 vs Cmax abdomen, 216 U.l-1). A twin-peak configuration of the concentration vs time curve with a significant second peak at 24 h was found after injection in the thigh but not after abdominal injection. In conclusion, the mean residence time was longer after administration in the thigh, probably due to delayed absorption, but bioavailability was not significantly different. Following injection in the thigh the concentration curve had two peaks. The differences may be due to regional variations in lymph flow and to physical activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased serum erythropoietin level during azathioprine treatment in renal transplant recipients

One hundred and six renal transplant patients were studied. During the first 12 months after renal transplantation all patients were treated with cyclosporine (Cy) and prednisone. At 12 months after transplantation the patients were randomly allocated to either conventional treatment with azathioprine (Az) and prednisone (group Az) or to continued treatment with Cy and prednisone (group Cy). Serum erythropoietin (s-EPO), glomerular filtration rate (GFR) and hematocrit (Hct) were measured at 12, 18 and 24 months after transplantation. s-EPO rose in the group Az from 19 U/l (mean) at 12 months to 28 U/l (p < 0.01) at 18 months and remained elevated at 24 months at 29 U/l compared with baseline level and with healthy subjects without anemia 18 U/l (p < 0.01). There was no significant change in s-EPO in group Cy during the study. The Hct in the two groups was not significantly different. GFR was the same in the two groups at 12 months and after 24 months. In conclusion, a switch from Cy to Az 1 year after renal transplantation results in a sustained rise in s-EPO which may in part represent a compensatory phenomenon to bone marrow suppression.

Effect of captopril on the renal veno-arterial gradient of erythropoietin and oxygen in unilateral renal artery disease

Twenty-nine patients with unilateral renal artery stenosis or occlusion were investigated. The veno-arterial gradient (VA-gradient) of erythropoietin (EPO), haemoglobin oxygen saturation and plasma renin activity (PRA) was determined separately in each kidney before and 1 h after angiotensin converting enzyme inhibition (ACE-inhibition). The VA-gradient of EPO and of hemoglobin oxygen saturation were the same in the affected and unaffected kidney during basal conditions. During ACE-inhibition the VA-gradient of EPO disappeared on the affected side but not on the unaffected side. A fall in s-EPO after ACE inhibition was demonstrated in the renal vein on the affected side (-1.4 U l-1, p < 0.01), in the contralateral vein (-0.8 U l-1, p < 0.01) and in the aorta (-0.6 U l-1, p < 0.01). The O2-gradients were reduced on both sides after captopril, from 10.8-7.5% (p < 0.04) on the affected side and from 10.8-9.0% (p < 0.04) on the contralateral. It is suggested that the stimulated renin-angiotensin system may be important for EPO production in the affected kidney in unilateral renal disease.

Elevated level of erythropoietin in congestive heart failure relationship to renal perfusion and plasma renin

BACKGROUND

In animal experiments reduction of renal perfusion can stimulate erythropoietin production. The relationship between renal haemodynamics and erythropoietin production is unknown in congestive heart failure.

OBJECTIVE

The aim was to study the relationship between serum erythropoietin and renal haemodynamics, plasma renin activity and haematocrit in patients with congestive heart failure and in healthy control subjects.

PATIENTS AND METHODS

Serum erythropoietin, renal plasma flow, glomerular filtration rate and plasma renin activity were determined in 14 patients with acyanotic congestive heart failure, and 36 healthy controls.

RESULTS

Serum erythropoietin was significantly elevated in congestive heart failure 26.6 U l-1 (median) compared with controls 17.0 U l-1 despite a normal haematocrit, and increased with the severity of congestive heart failure (New York Heart Association class II: 17 U l-1 [n = 4]; class III: 30 U l-1 [n = 5]; class IV: 45 U l-1 [n = 5]). Significant inverse correlations between serum erythropoietin and renal plasma flow (r = -0.60, P < 0.03), and between serum erythropoietin and glomerular filtration rate, were found in congestive heart failure but not in the control subjects. A significant positive correlation (r = 0.71, P < 0.03) was demonstrated between serum erythropoietin and plasma renin activity in congestive heart failure.

CONCLUSION

A severe reduction in renal perfusion in congestive heart failure appears to cause an increase in serum erythropoietin.

Atrial natriuretic peptide and parathyroid hormone (1-84) in relation to noradrenaline induced changes in blood pressure in uraemic and healthy subjects

In order to evaluate the hormonal regulation of blood pressure (BP) in uraemia 12 patients on chronic maintenance dialysis and 14 healthy controls were studied. BP and plasma concentrations of atrial natriuretic peptide (ANP), cyclic 3',5'-guanosine monophosphate (cGMP), and intact parathyroid hormone (PTH(1-84)) were determined before, during, and after a 60 min noradrenaline infusion 0.1 micrograms kg-1 body wt. min-1. Mean BP increased to the same extent in the uraemic patients (median 15 mmHg, range 6-25 mmHg) as in the controls (12 mmHg, 5-25 mmHg). ANP increased during noradrenaline infusion both in patients (7.2 to 8.3 pmol/l, medians, p < 0.01) and in controls (4.4 to 6.0 pmol/l, p < 0.01), and so did cGMP (patients: 31.6 to 35.9 nmol/l, p < 0.05; controls: 6.6 to 8.7 nmol/l, p < 0.01). PTH(1-84) was higher in the uraemic patients than in the controls, but was unchanged during noradrenaline infusion in both groups. Correlation analyses gave no evidence of a direct relation between BP and ANP, but basal PTH(1-84) was negatively correlated to basal mean BP in the patients (rho = -0.615, p < 0.05), but not in the controls. In conclusion, noradrenaline induced similar elevations of BP in dialysis patients as in healthy controls despite elevated ANP and PTH(1-84) in the patients, and ANP release was stimulated in both groups. PTH(1-84) may participate in blood pressure regulation in uraemic patients.

Renal and hormonal effects and tolerance of an ANP analogue in healthy man

The effect of an analogue of atrial natriuretic peptide (P-ANP) on glomerular filtration rate (GFR), renal plasma flow (RPF), urinary flow rate, urinary sodium excretion, tubular function estimated by the lithium clearance technique, and plasma levels of sodium and water homeostatic hormones, has been studied in 40 healthy males. Placebo or P-ANP 0.3, 1.5, or 3.0 micrograms.kg-1 bwt were given as an intravenous bolus injection to different groups. P-ANP did not cause any immediate change in GFR or RPF, but significant dose-dependent increases in filtration fraction, urinary flow rate and urinary excretion rate of sodium were detected during the first 30 min after administration. Proximal absolute and fractional tubular reabsorption and distal absolute tubular reabsorption of sodium did not change after injection of P-ANP, while the distal fractional reabsorption of sodium was reduced in a dose dependent manner during the first 30 min. Plasma angiotensin II and aldosterone were significantly increased 30 and 150 min after dosage, whereas plasma atrial natriuretic peptide, plasma arginine vasopressin, and urinary excretion of prostaglandin E2 were unchanged. Cyclic guanosine monophosphate both in plasma and urine were increased in a dose-dependent manner. P-ANP cause a significant reduction in diastolic blood pressure and an increase in pulse rate. Two subjects had vasovagal syncope 30-60 min after injection of P-ANP. It is concluded that P-ANP has natriuretic, diuretic and hypotensive properties in healthy man.

Physicians and exercise promotion

Regular exercise has been associated with numerous health benefits. In response, the promotion of regular exercise for patients has become a recommended component of preventive health care. The extent to which primary care physicians encourage their patients to exercise and the factors associated with exercise promotion are not well elucidated. We surveyed the attitudes and practices of 63 family physicians and 63 internists regarding exercise promotion to patients. We evaluated the associations between demography, cognition, belief, and behavior with exercise promotion. Several factors were associated with physicians' recommending exercise to their patients. A logistic regression model suggests that physicians who have a follow-up plan, who have been in practice over 10 years, who exercise themselves, and who estimate that more than 10% of their patients exercise encourage exercise in greater than or equal to 50% of their patients.

Attenuated renal excretory response to atrial natriuretic peptide in congestive heart failure in man

The renal and hormonal effects of atrial natriuretic peptide given as a bolus injection (2.0 micrograms/kg) were studied in 12 patients with congestive heart failure before and after treatment with captopril for 4 weeks and in 13 healthy control subjects. Atrial natriuretic peptide caused a rise in urinary excretion of sodium and urinary flow in the controls, whereas no increases were observed in the patients. Both proximal and distal fractional reabsorption of sodium, as evaluated by the lithium clearance technique, decreased less in the patients than in the controls. Basal plasma concentrations of atrial natriuretic peptide and cyclic guanosine monophosphate (cGMP), and the basal urinary excretion of cGMP, were elevated in the patients. The increases in both plasma and urinary cGMP after administration of atrial natriuretic peptide were blunted in heart failure. Basal glomerular filtration rate and renal plasma flow were reduced, and filtration fraction increased, in the patients. A positive correlation (r = 0.958, P less than 0.01) was found between renal plasma flow and the relative increase in urinary excretion of sodium in the patients with heart failure. Treatment with captopril did not improve the natriuretic and diuretic effect of exogenous atrial natriuretic peptide, but resulted in an increase in filtration fraction after administration of atrial natriuretic peptide not present before captopril.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormal tubular handling of sodium and water induced by atrial natriuretic peptide in essential hypertension

Atrial natriuretic peptide (ANP) was given as an intravenous bolus injection (2.0 micrograms kg-1) to 12 essential hypertensive patients (EH) and 13 normotensive control subjects (C) in order to study the effect of ANP on renal glomerular and tubular function using the lithium clearance technique. Urinary sodium excretion (EH, + 370% vs. C, + 120%; P less than 0.001) and urine volume (EH, + 137% vs. C, + 62%; P less than 0.01) increased significantly more in EH than in controls after ANP injection. Glomerular filtration rate, renal plasma flow, and plasma concentrations of angiotensin II, aldosterone and arginine vasopressin remained almost unchanged after ANP injection, whereas the filtration fraction increased to the same extent in both groups. Both proximal (EH, - 15% vs. C, - 5%; P less than 0.01) and distal fractional reabsorption (EH, - 12% vs. C, - 5%; P less than 0.01) of sodium decreased more markedly after ANP in EH than in controls. The increase in plasma cGMP and urinary excretion of cGMP was the same in the two groups. Mean blood pressure decreased and heart rate increased to the same extent in both groups. It is concluded that the increase in urinary sodium excretion and urine volume induced by ANP bolus injection is exaggerated in EH due to a more pronounced reduction in the reabsorption of sodium and water in both the proximal and the distal tubule.

Mechanisms of sodium retention in heart failure: relation to the renin-angiotensin-aldosterone system

Renal plasma flow (RPF), glomerular filtration rate (GFR), renal proximal tubular delivery of sodium and water evaluated by lithium clearance, and hormonal parameters were measured in 12 patients with congestive heart failure NYHA class II-IV before and after captopril treatment for 4 wk and in 13 healthy control subjects. RPF and GFR were significantly decreased in heart failure, whereas the filtration fraction (FF) was increased. Treatment with captopril increased RPF and decreased FF, whereas GFR was unchanged. Total and fractional urinary excretion of sodium were reduced in the patients compared with the controls, but increased after captopril. Fractional excretion of lithium was normal in heart failure and was increased by captopril. Atrial natriuretic peptide, guanosine 3',5'-cyclic monophosphate, and aldosterone in plasma were significantly elevated in heart failure and were reduced by treatment with captopril. Plasma renin activity was increased in patients, correlated inversely with RPF, and increased further after captopril treatment. It is concluded that the reduced sodium excretion in heart failure was caused by a combination of diminished glomerular filtration and enhanced tubular reabsorption beyond the proximal tubule and that treatment with captopril increased urinary sodium excretion partly due to an attenuated sodium reabsorption in the proximal tubule. The present data in patients with congestive heart failure are consistent with an increased intrarenal angiotensin II generation and an elevated plasma level of aldosterone being involved in the pathogenesis of the glomerular hemodynamic changes and the enhanced distal tubular reabsorption, respectively.

Comparison of calcium carbonate and aluminium hydroxide as phosphate binders on biochemical bone markers, PTH(1-84), and bone mineral content in dialysis patients

Bone mineral content, estimated by single-photon absorptiometry of the forearm, serum values of intact parathyroid hormone (PTH(1-84], osteocalcin, alkaline phosphatase, 1,25-dihydroxycholecalciferol (1,25(OH)2D3), and aluminium were determined during treatment with calcium carbonate (CaCO3) or aluminium hydroxide (Al(OH)3) in 11 dialysis patients participating in a randomised cross-over study. Each treatment period lasted 6 months. Serum phosphorus was maintained in the range 1.5-2.0 mmol/l. During Al(OH)3 treatment bone mineral content (BMC) decreased by 11% per half-year (mean), but only by 3% per half-year during CaCO3 treatment (P less than 0.05). Comparing the CaCO3 and Al(OH)3 periods the following differences were found: serum calcium increased during CaCO3 treatment, PTH(1-84) decreased (79% of initial values during CaCO3 versus 196% during Al(OH)3, mean area under curve, P less than 0.05), osteocalcin decreased (89% versus 117%, P less than 0.01), alkaline phosphatase decreased (92% versus 116%, P less than 0.05), and aluminium decreased (56% versus 189%, P less than 0.05). 1,25(OH)2D3 remained unchanged in both periods. No increase in soft-tissue calcification was demonstrated on X-ray of the shoulders in any of the periods. Thus, CaCO3 treatment seems to slow down loss of bone mineral content, and using CaCO3 as phosphate binder may have a more beneficial effect on the progression of uraemic bone disease than Al(OH)3 due to the reduction of hyperparathyroidism and bone turnover.

Differentiation between renovascular and essential hypertension by means of changes in single kidney 99mTc-DTPA clearance induced by angiotensin-converting enzyme inhibition

Blood pressure (BP), plasma renin concentration (PRC), and 99mTc-labeled diethylenetriaminepenta acetate (DTPA) renography with determination of single kidney 99mTc-DTPA clearance and parenchymal mean transit time (MTT) were measured in exactly the same way on two consecutive days in 14 patients with renovascular hypertension (RVH), unilateral renal artery stenosis in nine and bilateral stenosis in five, and ten patients with essential hypertension (EH). The examination on day 1 served as a control for day 2 during which captopril (25 mg) was given orally one hour before measurements of PRC and DTPA clearance. Blood pressure was reduced by captopril in both groups, but the maximum decrease in systolic BP was slightly more pronounced (P less than .01) in RVH (22%, median) than EH (13%). Plasma renin concentration increased to a much greater extent (P less than .01) after captopril in RVH (366%) than in EH (46%), Single kidney 99mTc-DTPA clearance was significantly (P less than .01) reduced (-39.5%) and MTT considerably prolonged (170%) on the affected/most affected side in RVH, but both parameters were only slightly changed or unchanged on the unaffected/least affected side (-6.5%, -2% respectively) and were not significantly changed in any of the sides in EH. The degree of renal artery stenosis was significantly correlated to the increase in PRC (rho = -0.786, n = 14 patients, P less than .01), to the reduction in single kidney 99mTc-DTPA clearance (rho = 0.729, n = 19 kidneys, P less than .01) and to the prolongation in MTT (rho = -0.785, n = 16 kidneys, P less than .01). By analysis of the captopril-induced changes in 99mTc-DTPA clearance and MTT, it was possible to predict the existence of a moderate to several renal artery stenosis in arterial hypertension with a very high degree of probability, and the use of changes in 99mTc-DTPA clearance and MTT after angiotensin-converting enzyme (ACE) inhibition may become a valuable tool in differentiation between RVH and EH.

Identification of LH/hCG receptors in rabbit uterus

Luteinizing hormone (LH) is believed to act via specific receptors to control gonadal steroidogenesis and reproductive processes. Recently A. J. Ziecik, P. D. Stanchev, and J. E. Tilton (Endocrinology 119:1159, 1986) reported surprisingly that LH/hCG receptors were present in porcine uterus, a tissue not known to be a target for LH action. We report herein the identification of high-affinity LH receptors in the rabbit uterus. Uteri from adult New Zealand white rabbits were homogenized in Tris-HCl, 0.25 M sucrose. After filtration and sequential centrifugation, a partially purified pellet containing receptors was obtained. This preparation was incubated with a trace (1300 cpm) (50 pg) 125I-labeled chorionic gonadotropin and with various unlabeled protein hormones. Receptor bound was separated from free hormone by centrifugation at 1000 g. Affinity was estimated by Woolf plot analysis. Specific binding sites for LH/hCG were identified. The following Kd's were calculated: human LH, 1.6 X 10(-11); hCG, 0.5 X 10(-11); human TSH, 1.3 X 10(-9); and human FSH, 7.85 X 10(-9). The reaction of human FSH and TSH with the receptor is best explained by LH contamination of these hormones. A similar preparation of rat liver showed that no binding sites were present. Rabbit ovarian LH receptors had a Kd slightly higher at 4.1 X 10(-11) than that of the uterine LH receptors. Rabbit ovarian receptors were present at 2.27 X 10(-13) M/mg protein compared to uterine receptors at 4.65 X 10(-15) M/mg protein. We conclude specific- and high-affinity binding sites (receptors) for LH are present in the rabbit uterus. The function of these receptors remains unknown.