[Value of the clinical examination in suspected meniscal injuries. A meta-analysis]. / Der verletzte Meniskus: Wie sicher ist die klinische Untersuchung? Eine Metaanalyse.

INTRODUCTION: The physical examination of the knee in cases of suspected meniscal tears serves to increase the probability of a correct diagnosis. Although there is a large variety of functional tests, the quality of each diagnostic test is controversially discussed. MATERIALS AND METHODS: Through a systematic literature search in Medline and the Cochrane Database two reviewers independently screened publications, evaluated each study for methodological quality and categorized them into levels of evidence (CEBM). Sensitivity, specificity, positive and negative predicted value, as well as positive and negative likelihood ratio (LR+/LR-) values were calculated in order to render the quality threshold of the physical examination in meniscus impairment. RESULTS: The Thessaly test (sensitivity: 91%, specificity: 97%, PPV: 97%, NPV: 91% LR+: 31.1, LR-: 0.1) revealed the highest test quality. Limited quality was shown for the Mc Murray test (sensitivity: 51%, specificity: 78%, PPV: 70%, NPV: 61%, LR+: 2.3, LR-: 0.6), "joint line tenderness" (sensitivity: 64%, specificity: 61%, PPV: 62%, NPV: 63%, LR+: 1.6, LR-: 0.6), the Apley-Grinding test (sensitivity: 38%, specificity: 84%, PPV: 71%, NPV: 58%, LR+: 2.4, LR-: 0.7) and the Ege test (sensitivity: 66%, specificity: 86%, PPV: 83%, NPV: 72%, LR+: 4.7, LR-: 0.4). Evidence for Steinman's test, Bragard's test and the meniscal signs of Böhler or Payr could not be tested. CONCLUSION: Meniscal injury can be detected by several functional tests. Using the Thessaly test can improve the physical examination by means of probability of the correct diagnosis, but the results are based on a single study. In patients with ambiguous findings in the physical examination or with suspected combined injury, further diagnostic procedures such as magnetic resonance imaging are necessary to confirm the diagnosis. In clinically certain cases the use of additional diagnostic imaging procedures should be avoided as other authors have shown that with few exceptions this has no influence on the therapy.

[Late patellar tendon rupture 10 years after anterior cruciate ligament reconstruction using a bone-patellar tendon-bone graft]. / Patellarsehnenruptur 10 Jahre nach vorderem Kreuzbandersatz durch Patellarsehnen-Knochen-Transplantat.

Autologous transplantation of the central third of the patella tendon with a bone-patellar tendon-bone (BTB) graft is one of the most commonly used techniques for anterior cruciate ligament (ACL) reconstruction. Frequently chosen alternative sources include semitendinosus and gracilis tendon autografts. The differences of opinion regarding graft sources mainly result from comparison of outcome and complications. Although higher donor site morbidity and postoperative extensor mechanism complications are postulated for bone-patellar tendon-bone grafts, patellar tendon ruptures following anterior cruciate ligament reconstruction are rarely reported in the literature. These predominantly occur during the early postoperative period. We present the case of a patellar tendon rupture in a healthy 36-year-old man, who suffered a skiing accident 10 years after uneventful ACL reconstruction with a BTB graft.

Function, osteoarthritis and activity after ACL-rupture: 11 years follow-up results of conservative versus reconstructive treatment.

ACL-reconstruction aims to restore joint stability and prevent osteoarthritis; however, malfunction and osteoarthritis are often the sequelae. Our study asks whether ACL-reconstruction or conservative treatment lead to better long-term results. In this retrospective cohort study, 136 patients with isolated ACL-rupture who had been treated by bone-ligament-bone transplant or conservatively were identified. Twenty-seven of these were excluded because of a revision operation in the 11.1 years follow-up period, leaving 109 patients (60 reconstructions and 49 conservatively treated) for evaluation based on clinical, radiological and internationally accepted knee-scores (Tegner, IKDC, Kellgren and Lawrence). An individual cohort study is classified as EBM level 2b according to the Oxford Centre of EBM. We observed significantly better knee-stability (P = 0.008) but more osteoarthritis (Grade II or higher) after ACL-reconstruction (42% vs. 25%). Physical activity levels were similar in both groups during the follow-up period (P = 0.16). Eleven years after ACL-rupture the physical activity levels are similar for both groups. After ACL-reconstruction, stability is higher as is osteoarthritis, whereby the result is not necessarily perceived as better subjectively. Specifically, this retrospective study yielded a 24% incidence of oseoarthrits 11 years after conservative management of ACL-rupture in patients not needing secondary surgery. The risk of secondary meniscal tears is reduced after ACL reconstruction, which reduces the negative effects of OA after surgery. The ultimate objective would be to achieve a good subjective outcome by conservative treatment followed by a rehabilitation program designed to keep secondary meniscus tears at a low level.

The SLAP lesion as a reason for glenolabral cysts: a report of five cases and review of the literature.

INTRODUCTION: Cysts in the spinoglenoidal or supraglenoidal incisura can be a cause of compression of the suprascapular nerve. There is agglomerated appearance of these cysts in combination with SLAP lesions. Hypothesis is SLAP lesions can lead to cysts in this region and should be repaired. MATERIAL AND METHODS: MRI of five patients (all male, four 30-40 years, one 75 years) showed cysts in the supralabral region. All were in combination with lesions of the superior glenoidal labrum (Type II or more). RESULTS: In two cases, in addition to cyst resection, the SLAP lesion was also repaired and symptoms disappeared completely and no recurrent cyst was detected in postoperative MRI. Two patients without SLAP repair showed recurrent cystic formation in MRI with similar complaints compared to their preoperative status. One patient (75 years) was treated primarily by puncture and afterwards with open resection of the cyst. His outcome was good in terms of activities of daily living without major pain. CONCLUSIONS: Our results are based on the assumption that cysts in the region of the spinoglenoidal/supraglenoidal incisura can originate from SLAP lesions. If a patient is suspected of having cysts in this region, the question of a SLAP lesion should be clarified. SLAP lesions should be repaired to avoid relapse. Arthroscopic repair of SLAP lesion can lead to the disappearance of symptoms in younger patients. In older patients puncture or resection of the ganglion alone may be an adequate therapeutic strategy.

[Development of a questionnaire for patient self-assessment of shoulder function based on the Rowe score]. / Entwicklung eines Patientenfragebogens, basierend auf dem Rowe-Score, zur Selbsterfassung der Schulterfunktion.

BACKGROUND: A questionnaire for patient self-assessment of shoulder function was designed. It was based on the internationally accepted Rowe score. METHOD: Explanations and photographs were added to the various parameters to make them easier to understand for the patients. A total of 95 patients completed the assessment form. The validity was tested by a correlation analysis comparing the questionnaire with the original score. RESULTS: The questionnaire demonstrated a reproducible and significant (p<0.001), very high correlation (r>0.9) in the overall results and a moderate to very high correlation within single parameters (r>0.68). CONCLUSION: Based on these results, it can be concluded that a valid and reproducible assessment of the original score is possible with the new questionnaire. Self-evaluation allows reliable assessment which is not dependent on the examiners or location, resulting in a higher number of patients reachable for follow-up studies.

Tunnel placement in anterior cruciate ligament (ACL) reconstruction: quality control in a teaching hospital.

Correct placement of the femoral and tibial bone tunnels is decisive for a successful anterior cruciate ligament (ACL) reconstruction. Our method of tunnel placement was evaluated as part of quality control at a teaching hospital. The emphasis was placed mainly on investigating the influence of surgical experience on tunnel placement, and the effect of tunnel position on the clinical outcome. Seventeen surgeons with different levels of experience (between 0 and >150 ACL reconstructions) performed endoscopic ACL repair in uniform technique from August 2000 to August 2003 on 50 patients (18 women, 32 men, age range 18-43 years). The patients were available to clinical and radiological follow-up after an average of 19 months. The clinical outcome was classified according to the International Knee Documentation Committee (IKDC) standard evaluation form. The femoral tunnel was evaluated according to the quadrant method of Bernard and Hertel; the position of the tibial bone tunnel was assessed according to the criteria of Stäubli and Rauschnig. The IKDC score revealed 47 (94%) patients with a normal (A) or nearly normal (B) knee joint at follow-up. According to the quadrant method, the femoral canal was situated on average at 29% in the saggital plane. The tibial tunnel was situated on average at 43% of the a.p. diameter of the tibial condyle. Statistical analysis of our data showed no significant correlation between tunnel placement and surgical expertise. However, a highly significant correlation was found (alpha<0.01) between the femoral position of the tunnel in the sagittal plane and the IKDC score. The more anterior the femoral canal, the poorer the IKDC score. The method of tunnel placement in ACL reconstruction being investigated here only showed slight dependence on surgical experience, whereby good short-term clinical outcomes were achieved. Therefore, the method is suitable for application at a teaching hospital. A far too anterior femoral tunnel placement will probably lead to a decline in the clinical result.

[Postoperatively recurring instability of the shoulder--a fault analysis in 46 cases]. / Die postoperative Rezidivinstabilität des Schultergelenks--Eine Ursachenanalyse in 46 Fällen.

AIM: The successful operative stabilization of the shoulder joint is a demanding surgical procedure. The causality of shoulder instability is complex with in some cases multiple lesions in different anatomical structures. The surgeon has to understand the complexity of factors causing instability in order to be therapeutically successful. The aim of the study was to document the intraoperative pathology in revision instability surgery. METHOD: 46 patients with recurrent postoperative instability were included (8 female, 38 male, follow-up > 12 months). After diagnostic arthroscopy an open revision surgery was performed in all cases. RESULTS: In 19 cases (40%) an insufficient surgical procedure was performed (inadequate capsular shift with worn out labral tissue). Selection of an incorrect surgical technique was the reason for revision in 12 patients (25%). Anamnestically 5 patients reported a re-injury, whereas objectively only one patient described an adequate trauma. The most frequent finding was an open rotator interval (persisting Foramen Weitbrecht), which was seen in 22 cases (46%). CONCLUSION: A stable range of motion of the shoulder is achieved by a variety of different factors, which leads in most instances to a combination of pathological changes in case of a dislocated shoulder. To understand the contributing factors of an instable shoulder joint is a necessity to carry out a successful surgical procedure.

[Reconstruction of big rotator cuff ruptures. A new technique of tendon refixation with the corkscrew suture anchor system]. / Die Rekonstruktion von grossen Rotatorenmanschettenrupturen. Eine neue Technik der Sehnenrefixation mit dem Corkscrew-Fadenankersystem.

Tendon retraction and fatty degeneration is a major problem in repair of massive rotator cuff tears. Especially in the transosseous refixation technique, a tension-free refixation cannot be obtained in all cases. The purpose of this prospective study was to evaluate the postoperative results using a new tension-free reinsertion technique with a Corkscrew suture anchor system. Thirty patients (25 males, 5 females) with complete one and two tendon tears underwent open rotator cuff repair (rupture of one tendon: n=14, 47%). The torn tendons were mobilized and reinserted medially to reduce tension. Medialization was achieved by inserting tendon near the osteochondral border in a bony trough. The number of implanted suture anchors ranged from 2 to 6 (mean: 3.56). The mean age was 56 years (39-68 years) with a follow-up of 24 months (17-33 months). In one patient physical and sonographic examination showed a complete and in two patients a partial rerupture. A temporarily frozen shoulder occurred in two cases. No infection or rejection response was seen. In no case was revision surgery necessary. No displacement or loosening of the Corkscrew anchors was noticed. The constant score improved from 45 points preoperatively to 85 points at the time of follow-up (mean). The Corkscrew suture anchor system in combination with the new suture technique offers the possibility of a stable reinsertion even in reduced calcified bone structure. This facilitates good conditions for stable fibroblastic healing. Our midterm results show good osseous union combined with a low rerupture rate.

[SLAP lesions as a cause of posterior instability]. / SLAP-Läsionen als Ursache einer posterioren Instabilität.

SLAP lesions disrupt the perilabral architecture, but so far there have been no reports about posterior instability due to SLAP lesions. In a prospective study of 30 patients with recurrent posterior instability, we found SLAP lesions as a reason for instability in three cases. The purpose of this study is to point out that SLAP lesions can be a cause of posterior instability. Thirty patients with clinical posterior shoulder instability underwent diagnostic arthroscopy before operative stabilization procedures, three of whom (three males, aged 29-51 years) showed a SLAP lesion (once case each of types II, III, and IV) as a cause of posterior instability. All three patients had a history of a fall on the outstretched arm. All patients underwent arthroscopic refixation of the labrum. After arthroscopic refixation of the SLAP lesions, two patients were completely stable (SLAP II and III), whereas one patient (SLAP IV) reported microinstability during overhead activity but complete stability during activity of daily living. The same patient complained about moderate pain in extreme external-flexion rotation with slightly reduced range of motion in external-flexion position. All other patients were free of pain and showed free range of motion. Our results demonstrate that SLAP lesions can be a cause for posterior shoulder instability. In our cases, posterior shoulder instability caused by SLAP lesions was successfully treated by arthroscopic refixation of the torn biceps anchor. When treating posterior shoulder instability, SLAP lesions should be taken into account.

[Development of a 3-dimensional method to determine the tibial slope with multislice-CT]. / Entwicklung eines 3-dimensionalen Messverfahrens zur Bestimmung des tibialen Gefälles im Spiral-CT.

AIM: The measurement or, respectively, the correction of the tibial slope is an important subject in the field of knee arthroplasty and in the procedure of cruciate ligament reconstruction. However, a valid value of the tibial slope cannot be obtained from the conventional plain X-rays in a reproducible way. The aim of this study was to evaluate the proximal tibial slope with a new CT measurement system and to compare the values with the X-ray method. METHOD: Using 6 cadaver tibiae, the antero-posterior slope of the proximal tibia was measured at 0 degrees, 2.5 degrees, 5 degrees, 10 degrees, 15 degrees, 20 degrees, 30 degrees internal rotation using the plain X-ray and spiral CT (3D-MPR reconstruction). Both methods were compared. RESULTS: The variation of the measurement of the tibial slope with the X-ray method was > 5 degrees even if the optimal 0 degrees rotation in the lateral view was applied. Moreover, the measurement error increased to 14 degrees while increasing the rotation of the tibia. Using the new CT system, the error was less than 3 degrees in all measurements. CONCLUSION: The measurement of the tibial slope in the conventional X-ray technique showed a high variation of the values depending on the rotation of the tibia in the lateral view. In contrast, the measurements with the new CT system represented a precise method with a small variation of the tibial slope values. For this reason detailed questions regarding the precise anatomy of the proximal tibia cannot be answered precisely with plain X-rays.

Self-organization of sorted patterned ground.

Striking circular, labyrinthine, polygonal, and striped patterns of stones and soil self-organize in many polar and high alpine environments. These forms emerge because freeze-thaw cycles drive an interplay between two feedback mechanisms. First, formation of ice lenses in freezing soil sorts stones and soil by displacing soil toward soil-rich domains and stones toward stone-rich domains. Second, stones are transported along the axis of elongate stone domains, which are squeezed and confined as freezing soil domains expand. In a numerical model implementing these feedbacks, circles, labyrinths, and islands form when sorting dominates; polygonal networks form when stone domain squeezing and confinement dominate; and stripes form as hillslope gradient is increased.

Multislice CT imaging of pulmonary embolism.

In recent years CT has been established as the method of choice for the diagnosis of central pulmonary embolism (PE) to the level of the segmental arteries. The key advantage of CT over competing modalities is the reliable detection of relevant alternative or additional disease causing the patient's symptoms. Although the clinical relevance of isolated peripheral emboli remains unclear, the alleged poor sensitivity of CT for the detection of such small clots has to date prevented the acceptance of CT as the gold standard for diagnosing PE. With the advent of multislice CT we can now cover the entire chest of a patient with 1-mm slices within one breath-hold. In comparison with thicker sections, the detection rate of subsegmental emboli can be significantly increased with 1-mm slices. In addition, the interobserver correlation which can be achieved with 1-mm sections by far exceeds the reproducibility of competing modalities. Meanwhile use of multislice CT for a combined diagnosis of PE and deep venous thrombosis with the same modality appears to be clinically accepted. In the vast majority of patients who receive a combined thoracic and venous multislice CT examination the scan either confirms the suspected diagnosis or reveals relevant alternative or additional disease. The therapeutic regimen is usually chosen based on the functional effect of embolic vascular occlusion. With the advent of fast CT scanning techniques, also functional parameters of lung perfusion can be non-invasively assessed by CT imaging. These advantages let multislice CT appear as an attractive modality for a non-invasive, fast, accurate, and comprehensive diagnosis of PE, its causes, effects, and differential diagnoses.

[Diagnosis of lung embolism with multislice spiral CT]. / Diagnostik der Lungenembolie mit der Mehrschicht-Spiral-CT.

In recent years CT has been established as the method of choice for the diagnosis of central pulmonary embolism to the level of the segmental arteries. The key advantage of CT over competing modalities is the reliable detection of relevant alternative or additional disease causing the patient's symptoms. Although the clinical relevance of isolated peripheral emboli remains unclear, the alleged poor sensitivity of CT for the detection of such small clots has to date prevented the acceptance of CT as the gold standard for diagnosing pulmonary embolism. With the advent of multislice CT we can now cover the entire chest of a patient with 1-mm slices within one breath-hold. In comparison with thicker sections the detection rate of subsegmental emboli can be significantly increased with 1-mm sections. In addition the interobserver correlation which can be achieved with 1-mm sections by far exceeds the reproducibility of competing modalities. Meanwhile use of multislice CT for a combined diagnosis of pulmonary embolism and deep venous thrombosis with the same modality appears to be clinically accepted. In the vast majority of patients who receive a combined thoracic and venous multislice CT examination the scan either confirms the suspected diagnosis or reveals relevant alternative or additional disease. The therapeutic regimen is usually chosen based on the functional effect of embolic vascular occlusion. With the advent of fast CT scanning techniques, also functional parameters of lung perfusion can be non-invasively assessed by CT imaging. These advantages let multislice CT appear as an attractive modality for a non-invasive, fast, accurate and comprehensive diagnosis of pulmonary embolism, its causes, effects and differential diagnoses.

SmMAK16, the Schistosoma mansoni homologue of MAK16 from yeast, targets protein transport to the nucleolus.

The SmMAK16 gene from Schistosoma mansoni was cloned by chance when an adult worm cDNA library was probed with antiserum to affinity-purified S. mansoni GSH S-transferases. SmMAK16 encodes a hydrophilic protein of 259 amino acids with a molecular mass of 31 kDa. The protein shares 43% sequence identity and 66% similarity to the nuclear protein MAK16 of Saccharomyces cerevisiae that has been implicated both in cell cycle progression and biogenesis of 60S ribosomal subunits. Both proteins display a similar degree of sequence similar to the hypothetical protein CeMAK16 from Caenorhabditis elegans. These proteins share a number of apparent protein motifs, including two nuclear localization signals (NLS), multiple sites for phosphorylation by protein kinase CK2 and four conserved cysteine residues that resemble a zinc binding domain. SmMAK16 mRNA is more highly expressed in adult female worm than males. Recombinant SmMAK16 was phosphorylated by human protein kinase CK2. When chimeric constructs containing SmMAK16 fused the green fluorescent protein (GFP) were transiently transfected into COS-7s cells, the reporter was localized not in nuclei, but exclusively in nucleoli. The yeast and nematode homologues were likewise able to direct nucleolar accumulation of the fluorescent reporter. The high degree of sequence conservation together with the ability to direct nucleolar protein transport supports the hypothesis that MAK16 proteins play a key role in the biogenesis of 60S subunits.

Prolactin receptor heterogeneity in bovine fetal and maternal tissues.

Study of diverse PRL actions at a variety of fetal and maternal targets during pregnancy is complicated by receptor heterogeneity and multiple ligands circulating at this time. In the present studies, we have examined PRL receptors at a variety of potential targets by reverse transcription-PCR and Western analysis. Bovine tissues contain two different transcripts for the PRL receptor; the one that encodes a short form includes an additional 39 bases at a position identical to the deviation from the long form found in rodents and sheep. Western analyses of PRL receptors in microsomal fractions from various maternal and fetal tissues revealed considerable size heterogeneity. Collectively, the larger immunoreactive moieties (apparent Mr 100 kDa or greater) and the smaller species (47-55 kDa) correlated well with the relative abundance of the transcripts for the different forms of the receptor and varied considerably among tissues. N-Glycosylation was shown to be the major, but not the only, modification of both receptor forms when transiently transfected into COS-7 and END-6.2 cells. Much of the short form could be reduced to the mobility predicted from the complementary DNA by culture with tunicamycin; this was not true of the long form, suggesting modifications specific for its cytoplasmic domain. Differences in the pattern of immunoreactive species in the COS-7 and END-6.2 cells are consistent with cell-specific modifications. The ability of these receptor forms to mediate a transcriptional response to PRL and its placental relative, placental lactogen, was evaluated with a PRL response element inserted upstream from a thymidine kinase promoter/reporter gene construct transiently transfected into CHO-K1 cells. Both hormones were able to stimulate reporter gene expression through the long form, but not the short form, of the receptor. These studies will facilitate examination of tissue-specific actions of PRL and related hormones during pregnancy.

Microalbuminuria and borderline-increased albumin excretion determined with a centrifugal analyzer and the Albumin Blue 580 fluorescence assay.

We report a new automated fluorescence assay for determination of albumin in urine. The dye Albumin Blue 580 specifically binds to albumin with exhibition of strong red fluorescence. The albumin concentration is calculated from emission intensity at 616 nm (excitation at 590 nm) and a calibration curve. Two Cobas Fara programs cover working ranges of 2-200 and 1-50 mg/L with detection limits of 1.4 and 0.4 mg/L, respectively. Within-run CVs (n = 10) ranged from 1.7% (189 mg/L) to 8.9% (7.2 mg/L) for 2-200 mg/L and from 2.9% (43.3 mg/L) to 5.7% (2.3 mg/L) for the 1-50 mg/L range. A test of urine samples (n = 100) submitted to routine analysis gave results that agreed well with those by the Behring nephelometric assay: AB 580 = 0.922 (+/-0.010) BNA + 4.16 (+/-0.78). No interference was detected from other urine components, including several proteins and 46 drugs. The high specificity and sensitivity make the method ideal for determination of microalbuminuria. In addition, the method is fast, inexpensive, and well-suited for clinical laboratory application and thus may be used instead of immunoassays.

Regulation of interleukin (IL)-1alpha, IL-1beta, and IL-6 expression by growth hormone and prolactin in bovine thymic stromal cells.

Growth hormone (GH) and prolactin (PRL) have been implicated in T-cell development, but relatively little is known about the mechanism(s) of their actions on the multiple cell types in this complex tissue. Here, we investigated the effects of GH and PRL on the expression of interleukin (IL)-1alpha, IL-1beta and IL-6 in thymic stromal cells (TSC). These cytokine mRNAs were increased by GH, PRL and placental lactogen (PL) in primary cultures prepared from mid-gestational fetuses in a dose-dependent manner. IL-1 receptor antagonist (IL-1ra) abolished the hormone-induced IL-6 expression, suggesting that the induction of IL-6 was secondary to IL-1 activity. To examine the effects of these hormones on an individual cell type and develop a system in which signalling mechanisms can be studied, we generated immortalized cell lines using a strategy of conditional transformation. In the cell line, TSC-936, which displayed vimentin-positive staining and morphological characteristics of mesenchymal cells, both GH and PRL increased levels of steady-state mRNAs for IL-1alpha and IL-1beta. Nuclear run-on analysis revealed that the transcription rate of the IL-1beta gene was significantly increased by GH and PRL at 30 and 60 min, respectively, but that for IL-1alpha was not significantly changed, suggesting the possibility of an alternative mechanism mediating this response. These data suggest that modulation of cytokine gene expression is one mechanism by which GH and PRL facilitate thymic development and T-cell maturation.

Purification and properties of placental prolactin-related protein-I.

We used sucrose density gradient centrifugation, size exclusion chromatography, and high-pressure reversed-phase chromatography in the purification of bovine prolactin-related protein-I (bPRP-I) to homogeneity from a secretory granule-enriched fraction of fetal cotyledon. Amino terminal sequence was unambiguous, consistent with the nucleic acid sequence of the cDNA 50 codons distal to the initial AUG in the open reading frame, and began with the residues: RKSFTDRFMNAASLSHDFY. This is distinct from the signal peptide cleavage site predicted by the algorithm of von Heijne (1986) as well as that expected by comparison with other members of the growth hormone/prolactin family of hormones. The level of bPRP-I in uterine fluid was sufficient to detect by Western blot of unfractionated material and estimated as at least 0.65 microM. In contrast, bPRP-I was undetectable in the serum by this method. Interaction of [125I]-bPRP-I with high molecular weight serum components interfered with its measurement by radio-immunoassay, and could be replicated with purified alpha 2-macroglobulin with an apparent KD of about 0.41 microM. Thus, the bPRP-I gene product is processed secreted and distributed in a manner consistent with a paracrine action at the materno-fetal interface.

Bovine placental prolactin-related hormones.

The bovine placenta, like that of rodents and primates, synthesizes members of the PRL/GH gene family, which may assist the pituitary hormones or perform unique functions during pregnancy. Bovine placental lactogen (bPL) potentially may act through.three receptors: as an agonist or partial antagonist at the PRL and GH receptors, and via an apparently specific receptor in the endometrium. A large distinct subfamily of diverse primary structure, including bovine PRL-related protein I (bPRP-I), evidently does not act via these receptors. Advances in our understanding of hormone-receptor interactions for this gene family have provided new tools to study the role of these hormones in the successful pregnancy.