Effects of horse housing on musculoskeletal system post-exercise recovery

This study examined the effects of two housing systems (control housing and loose housing) on musculoskeletal condition during recovery from race-like exercise in Standardbred horses. The hypothesis was that a loose housing system provides better conditions for musculoskeletal recovery than the control housing. Eight adult geldings (mean age 11 years) were used in a study with a cross-over design, with the control housing (CH) and loose housing (LH) treatments each run for 21 days. The horses had ad libitum access to forage and performed two similar race-like exercise tests (ET), on day 7 and day 14 in each treatment. Blood samples were collected before ET, at finish line, and at 7, 22, and 44 h of recovery and analysed for the muscle enzyme activities of creatine kinase and amino transferase. Before and three days after ET, hind leg fetlock joint region circumference and diameter, joint range of motion in right hock and carpus, mechanical nociceptive threshold in back muscle, and movement asymmetry were recorded. Overall circumference and overall diameter of hind fetlock joint region were lower in LH horses than CH horses (P=0.045 and P=0.017, respectively), but no other differences were observed. In conclusion, a loose housing system did not alter the recovery of musculoskeletal condition other than preventing a post exercise enlargement of the circumference and diameter of the hind fetlock joint region.

Strategies discussed at the XIIth international conference on Kangaroo mother care for implementation on a countrywide scale

AIM

Building strategies for the country-level dissemination of Kangaroo mother care (KMC) to reduce the mortality rate in preterm and low birth weight babies and improve quality of life. KMC is an evidence-based healthcare method for these infants. However, KMC implementation at the global level remains low.

METHODS

The international network in Kangaroo mother brought 172 KMC professionals from 33 countries together for a 2-day workshop held in conjunction with the XIIth International KMC Conference in Bogota, Colombia, in November 2018. Participants worked in clusters to formulate strategies for country-level dissemination and scale-up according to seven pre-established objectives.

RESULTS

The minimum set of indicators for KMC scale-up proposed by the internationally diverse groups is presented. The strategies for KMC integration and implementation at the country level, as well as the approaches for convincing healthcare providers of the safety of KMC transportation, are also described. Finally, the main aspects concerning KMC follow-up and KMC for term infants are presented.

CONCLUSION

In this collaborative meeting, participants from low-, middle- and high-income countries combined their knowledge and experience to identify the best strategies to implement KMC at a countrywide scale.

Intersegmental strategies in frontal plane in moderately-skilled riders analyzed in ridden and un-mounted situations

The symmetry of the rider is highly relevant, and in the equestrian community it is generally thought that a symmetrical rider has a better possibility to influence the horse in an optimal way. The aim of the study was to analyse and compare frontal plane kinematics of the core body segments in ten riders while riding and while rocking a balance chair from side-to-side. It was hypothesized that the riders were asymmetrical in relation to their intersegmental strategies when comparing between left and right directions and that individual riders would display the same postural strategies when riding and when rocking the balance chair. Ten moderately-skilled riders wore a full-body marker set that was tracked by a motion capture system as they rocked a balance chair from side to side. Inertial measurement units attached to the head, trunk and pelvis were used to measure the segmental movements while riding in left and right directions. Roll rotation data for head, trunk and pelvis were averaged over available strides/cycles. Results from mixed models showed that the riders were asymmetric when comparing riding in left vs right directions, for example the trunk was rotated 19° to the right on the right circle and 14° to the left on the left circle, on average. Riders adopted the same asymmetrical posture whether they were riding in the left or right direction on straight lines, circles or leg yielding. A significant relationship was found between postural asymmetries when riding and when rocking the balance chair, one degree of pelvis or head roll asymmetry on the chair predicted 2.4 (SE 0.9) degrees of asymmetry while riding. Future studies may investigate the value of seated, off-horse postural training for improving rider symmetry and thereby equestrian performance.

Head, trunk and pelvic kinematics in the frontal plane in un-mounted horseback riders rocking a balance chair from side-to-side

For efficient rider-horse communication, the rider needs to maintain a balanced position on the horse, allowing independent and controlled movements of the rider’s body segments. The rider’s balance will most likely be negatively affected by postural asymmetries. The aims of this study were to evaluate inter-segmental symmetry of movements of the rider’s pelvis, trunk, and head segments in the frontal plane while rocking a balance chair from side to side and to compare this to the rider’s frontal plane symmetry when walking. Frontal plane rotations (roll) of the pelvis, trunk and head segments and relative translations between the segments were analysed in twenty moderately-skilled riders seated on a balance chair and rocking it from side to side. Three-dimensional kinematic data were collected using motion capture video. Principal component analysis and linear regression were used to evaluate the data. None of the riders displayed a symmetrical right-left pattern of frontal plane rotation and translation in any of their core body segments. The intersegmental pattern of asymmetries varied to a high degree between individuals. The first three principal components explained the majority of between-rider variation in these patterns (89%). A significant relationship was found indicating that during walking, when foot eversion was present on one side, pelvic/trunk roll during rocking the chair was asymmetric and larger to that same side (P=0.02, slope=0.95 in degrees). The inter-individual variation in the rider’s intersegmental strategies when rocking a balance chair was markedly large. However, there was a significant association to the rider’s foot pattern while walking, suggesting consistent intra-individual patterns over multiple situations. Although further studies are needed to confirm associations between the findings in this study and rider asymmetry while riding, riders’ postural control can likely be improved and this may enhance their sport performance.

Validation of two simple, objective tools for the assessment of synovial swelling in the equine fetlock region

Simple objective assessment tools are essential to monitor the efficacy of therapeutic interventions used in clinical settings. The purpose of present study was to investigate different ways of assessing synovial swelling of the equine fetlock region: tape measure and slide calliper, and to examine the method’s inter- and intra-examiner reliability. The hypotheses were that inter-examiner reliability would be fair and intra-examiner reliability strong. Measurements were performed on both hind limbs, on 16 horses. Palpation was done once for each limb, over the plantar pouch of the fetlock joint and the plantar digital flexor tendon sheath (PDFTS). Tape measure and slide calliper registrations were made, in triplicate by two independent assessors blinded to the measurements, horizontally over the fetlock joint and PDFTS areas, respectively. Intra-class correlation was used to measure inter- and intra-examiner reliability. The inter-examiner reliability was fair for the tape measurement of the plantar pouch of the fetlock joint, and almost perfect for the PDFTS. It was moderate for the slide calliper assessment of the PDFTS and almost perfect for the plantar pouch. The intra-examiner reliability was almost perfect for tape measure and slide calliper assessment, for the plantar pouch and PDFTS, respectively. Our results support our hypothesis and indicate that tape measure and slide calliper measurement of plantar pouch of the fetlock joint and PDFTS can be reliably performed by the same therapist. Slide calliper and circumference tape measures are promising objective techniques for assessing synovial swelling of the equine fetlock region.

Distributed decision making in action: diagnostic imaging investigations within the bigger picture

INTRODUCTION

Decision making in the health care system - specifically with regard to diagnostic imaging investigations - occurs at multiple levels. Professional role players from various backgrounds are involved in making these decisions, from the point of referral to the outcomes of the imaging investigation. The aim of this study was to map the decision-making processes and pathways involved when patients are referred for diagnostic imaging investigations and to explore distributed decision-making events at the points of contact with patients within a health care system.

METHOD

A two-phased qualitative study was conducted in an academic public health complex with the district hospital as entry point. The first phase included case studies of 24 conveniently selected patients, and the second phase involved 12 focus group interviews with health care providers. Data analysis was based on Rapley's interpretation of decision making as being distributed across time, situations and actions, and including different role players and technologies.

RESULTS

Clinical decisions incorporating imaging investigations are distributed across the three vital points of contact or decision-making events, namely the initial patient consultation, the diagnostic imaging investigation and the post-investigation consultation. Each of these decision-making events is made up of a sequence of discrete decision-making moments based on the transfer of retrospective, current and prospective information and its transformation into knowledge.

CONCLUSION

This paper contributes to the understanding of the microstructural processes (the 'when' and 'where') involved in the distribution of decisions related to imaging investigations. It also highlights the interdependency in decision-making events of medical and non-medical providers within a single medical encounter.

Does foot pronation in unmounted horseback riders affect pelvic movement during walking?

Foot pronation is a common postural condition that is related to postural asymmetry, and that may affect performance in a variety of sports. The aim of this study was to evaluate whether unmounted riders (n=18) with predominantly right or left foot pronation had an increased contralateral pelvic drop during stance of the more pronated foot when walking. This was a preliminary step toward investigating the effects of foot pronation during riding. Kinematic data were collected in 3D (250 Hz) using eight motion capture cameras during walking. The amount of foot pronation was measured by summing eversion and external rotation, and it was analysed in relation to maximal pelvic drop during stance. The results showed that during walking, the majority of the riders had significantly greater contralateral pelvic drop when the foot with the higher degree of pronation was in early stance. If the demonstrated postural asymmetry carries over to other activities where weight is distributed to the feet, e.g. at riding when the riders feet exert a force against the stirrups, this may affect the rider’s performance. Further studies are needed to describe the influence of foot pronation in mounted horseback riders.

Dual-modality probe intended for prostate cancer detection combining Raman spectroscopy and tactile resonance technology--discrimination of normal human prostate tissues ex vivo

Prostate cancer is the most common cancer for men in the western world. For the first time, a dual-modality probe, combining Raman spectroscopy and tactile resonance technology, has been used for assessment of fresh human prostate tissue. The study investigates the potential of the dual-modality probe by testing its ability to differentiate prostate tissue types ex vivo. Measurements on four prostates show that the tactile resonance modality was able to discriminate soft epithelial tissue and stiff stroma (p < 0.05). The Raman spectra exhibited a strong fluorescent background at the current experimental settings. However, stroma could be discerned from epithelia by integrating the value of the spectral background. Combining both parameters by a stepwise analysis resulted in 100% sensitivity and 91% specificity. Although no cancer tissue was analysed, the results are promising for further development of the instrument and method for discriminating prostate tissues and cancer.

Evaluation of skin displacement in the equine neck

Kinematic studies, using reflective skin markers, are commonly used to investigate equine joint motion in equitation science and for rehabilitation purposes. In order to interpret the registrations accurately, the degree of skin displacement has been described for the limbs and back, but not yet for the neck. The aim of the present study was to measure sagittal plane skin displacement in the equine neck. Radiopaque skin markers were applied to the skin over the first six cervical vertebrae of six healthy horses. Latero-lateral radiographs were taken in three standardised neck positions in the sagittal plane: control (horizontal neck), ‘on the bit’ and ‘nose to carpus’. The scales of the images were normalised and calculation of skin displacement was done by use of a coordinate system, dividing the displacement along an x-axis parallel to the vertebra's longitudinal axis and a y-axis perpendicular to the x-axis. Mixed models analysis was employed to study the differences in distances in x- and y-directions, and statistical significance was set to PÃ0.05. Between control and ‘nose to carpus’ positions, there were significant differences in skin marker locations, relative to the underlying vertebrae, in the x-direction for C1-6, and in y-direction for C3-6. Between normal and ‘on the bit’ positions, there were significant difference in both x- and y-directions for C6. Differences in marker locations along x- and y-axes, respectively, were 3±9 mm and 44±14 mm. The outcome of this study indicates that skin displacement should be considered when investigating equine neck motion with skin marker methodology.

Goniometry: is it a reliable tool to monitor passive joint range of motion in horses?

REASONS FOR PERFORMING STUDY

Simple objective assessment tools are essential to monitor the clinical efficacy of therapeutic interventions used in equine orthopaedics and rehabilitation. In human medicine, goniometry is a validated tool to quantify restrictions in joint range of motion (ROM); however, the technique is not validated in horses.

OBJECTIVES

To validate 2 different goniometry techniques for the measurement of passive flexion of the fetlock, carpus and hock by examining; 1) the intra- and inter-tester reliability; 2) the differences between 2 goniometry techniques and 3) differences between standing and anaesthetised horses.

METHODS

The study is composed of three parts: 1) the intra- and inter-tester reliability was examined on 10 horses, where each horse was assessed by 5 pairs of testers measuring ROM with a universal goniometer; 2) the differences between 2 goniometry techniques were examined on 14 horses, each assessed by 2 investigators (either working in pairs with one investigator holding the limb and the other measuring the joint angle, or working individually at the same time holding and measuring); 3) on 6 horses, the differences between standing and anaesthetised horses were assessed by 2 investigators with the same techniques as described above. Nonparametric tests (Mann-Whitney, Wilcoxon sign-rank) and Intraclass Correlation Coefficient (ICC) were used for statistical analysis (P < 0.05).

RESULTS

1) The intra-tester reliability was high to excellent (ICC 0.8-1) and the inter-tester reliability low to average (ICC 0.1-0.5); 2) significant differences in joint ROM were registered in carpus and hock when measuring in pairs compared to singly and 3) significant differences in joint ROM were registered measuring anaesthetised compared to standing horses.

CONCLUSIONS

As shown in human studies, goniometry is a promising tool in documenting passive flexion of fetlock, carpus and hock, if used by the same investigator. However, additional studies are needed for further validation.

Evaluation of neuromuscular electrical stimulation on fibre characteristics and oxidative capacity in equine skeletal muscles

REASONS FOR PERFORMING STUDY

Neuromuscular electrical stimulation (NMES) is used to increase or maintain muscle strength during rehabilitation. Human studies investigating different protocols show that some treatments induce changes in muscle characteristics. Despite the frequent use of NMES in horses, no studies have been published describing its efficacy.

OBJECTIVES

To investigate the effects of a NMES protocol on equine fibre types and areas, glycogen concentrations and enzyme activities.

METHODS

NMES was administrated to m. gluteus medius and m. longissimus dorsi, on one side of 6 healthy Standardbred horses. The contralateral side of each muscle served as a nonstimulated control. The horses were stimulated at 50 Hz a day, with 21-39 mA, for 45-60 min, 5 days a week for 4 weeks. Needle biopsies were obtained from the muscles on both sides before and after the experimental period. Muscle samples were analysed for fibre type proportions and area using histochemical methods and for glycogen and enzyme activities (citrate synthase, 3-OH-acyl CoA dehydrogenase, hexokinase and lactate dehydrogenase) using biochemical methods. Muscle contractions at the location and depth of the muscle biopsy were confirmed by diagnostic ultrasound. Nonparametric tests (Mann-Whitney, Wilcoxon sign-rank) were used for statistical analysis.

RESULTS

No significant differences were observed in the percentage of types I, IIA or IIX fibres, fibre areas, glycogen levels or enzyme activities either when comparing stimulated and nonstimulated muscles before and after the NMES treatment, or when comparing the left and right muscle samples.

CONCLUSIONS

The NMES treatment was well tolerated by the horses, but the present protocol did not induce significant muscle adaptations. Further studies are needed to describe the effect of more intense and/or prolonged NMES treatment protocols on muscles of healthy horses, and to describe if stimulation protocols induce positive changes in atrophied muscles.

Nuclear androgen receptor staining in bone metastases is related to a poor outcome in prostate cancer patients

Androgen receptors (ARs) are probably of importance during all phases of prostate cancer (PC) growth, but their role in bone metastases is largely unexplored. Bone metastases were therefore collected from hormone-naive (n=11), short-term castrated (n=7) and castration-resistant PC (CRPC, n=44) patients by biopsy (n=4) or at surgery to alleviate symptoms from metastases complications (metastasis surgery, n=58), and immunostained for nuclear ARs, Ki67, active caspase-3, prostate-specific antigen (PSA) and chromogranin A, and results were related to serum PSA, treatments and outcome. Nuclear AR immunostaining was decreased and apoptosis was increased, but cell proliferation remained largely unaffected in metastases within a few days after surgical castration. In CRPC patients, nuclear AR staining of metastases was increased when compared to short-term castrated patients. The nuclear AR staining score was related to tumour cell proliferation, but it was not associated with other downstream effects of AR activation such as apoptosis and PSA staining, and it was only marginally related to the presence of neuroendocrine tumour cells. Serum PSA at metastasis surgery, although related to outcome, was not associated with AR staining, markers of metastasis growth or PSA staining in metastases. High nuclear AR immunostaining was associated with a particularly poor prognosis after metastasis surgery in CRPC patients, suggesting that such men may benefit from the potent AR blockers now tested in clinical trials.

Defocused CO2 laser on equine skin: a histological examination

REASONS FOR PERFORMING STUDY

No studies have been published on effects of treatment with a defocused beam carbon dioxide (CO2) laser on equine skin histology. A better understanding of this will help to define how lasers should be used, in order to reduce potential side effects.

OBJECTIVE

To describe the acute effects of different doses of defocused CO2 laser, ranging from therapeutic to surgical levels, on equine skin.

METHODS

Defocused CO2 laser was administered to the skin in the hamstrings (91 J/cm2), fetlock (137 J/cm2) and loin (450 J/cm2) areas of 13 Standardbred horses. The acute effects on skin histology were examined 90 min after the end of therapy.

RESULTS

Mild changes with focal spongiosis and subepidermal clefts were found after 91 J/cm2 irradiation and more severe changes with diffuse subepidermal clefts after the 137 J/cm2 dose. A homogeneous eosinophilic acellular zone of dermis and destruction of adnexal structures, and significant thinning of the epidermis was observed after the 450 J/cm2 dose.

CONCLUSIONS

The present study indicates acute dose-dependent changes in equine skin histology after laser treatment Severe tissue damage was induced using a 450 J/cm2 dose.

POTENTIAL RELEVANCE

To reduce the potential side effects of defocused CO2 laser treatment, the laser parameters must be carefully evaluated. Caution should be taken if doses higher than 91 J/cm2 (16 W, 4 min, and 42 cm2) are used in irradiation of equine skin.

An image analysis method for prostate tissue classification: preliminary validation with resonance sensor data

Resonance sensor systems have been shown to be able to distinguish between cancerous and normal prostate tissue, in vitro. The aim of this study was to improve the accuracy of the tissue determination, to simplify the tissue classification process with computerized morphometrical analysis, to decrease the risk of human errors, and to reduce the processing time. In this article we present our newly developed computerized classification method based on image analysis. In relation to earlier resonance sensor studies we increased the number of normal prostate tissue classes into stroma, epithelial tissue, lumen and stones. The linearity between the impression depth and tissue classes was calculated using multiple linear regression (R(2) = 0.68, n = 109, p < 0.001) and partial least squares (R(2) = 0.55, n = 109, p < 0.001). Thus it can be concluded that there existed a linear relationship between the impression depth and the tissue classes. The new image analysis method was easy to handle and decreased the classification time by 80%.

Nordic consensus on treatment of undescended testes

AIM

To reach consensus among specialists from the Nordic countries on the present state-of-the-art in treatment of undescended testicles.

METHODS

A group of specialists in testicular physiology, paediatric surgery/urology, endocrinology, andrology, pathology and anaesthesiology from all the Nordic countries met for two days. Before the meeting, reviews of the literature had been prepared by the participants.

RECOMMENDATIONS

The group came to the following unanimous conclusions: (1) In general, hormonal treatment is not recommended, considering the poor immediate results and the possible long term adverse effects on spermatogenesis. Thus, surgery is to be preferred. (2) Orchiopexy should be done between 6 and 12 months of age, or upon diagnosis, if that occurs later. (3) Orchiopexy before age one year should only be done at centres with both paediatric surgeons/urologists and paediatric anaesthesiologists. (4) If a testis is found to be undescended at any age after 6 months, the patient should be referred for surgery--to paediatric rather than general surgeons/urologists if the boy is less than one year old or if he has bilateral or non-palpable testes, or if he has got relapse of cryptorchidism.

Association between the presence of bacterial 16S RNA in prostate specimens taken during transurethral resection of prostate and subsequent risk of prostate cancer (Sweden)

OBJECTIVE

To study bacterial 16S RNA in archival prostate samples from 352 patients with benign prostate hyperplasia (BPH) and evaluate whether the presence of bacterial DNA was different in those who later developed prostate cancer (n = 171) and in the matched controls that did not progress to cancer (n = 181).

METHODS

16S DNA PCR followed by cloning and sequencing the positive samples.

RESULTS

In 96/352 (27%) of the prostate tissue specimens 16S RNA were detected. Sequence analysis revealed Propionibacterium acnes as the predominant microorganism (23% of 16S RNA positive patients). The second most frequent isolate-Escherichia coli was found in 12 (12%) patients. The other isolates included Pseudomonas sp. (3 patients), Actinomyces sp. (2), Streptococcus mutans (1), Corynebacterium sp. (2), Nocardioides sp. (1), Rhodococcus sp. (1) Veillonella sp. (2). In P. acnes positive samples 62% exhibited severe histological inflammation versus 50% in the bacteria-negative group (p = 0.602). The presence of P. acnes in the prostate was associated with prostate cancer development (OR 2.17, 95% CI 0.77-6.95).

CONCLUSIONS

This study has revealed P. acnes as the most common bacteria in the prostate in BPH. Further studies are needed to clarify its role in contributing to the development of prostatic inflammation and prostate cancer.

Effect of defocused CO2 laser on equine tissue perfusion

Treatment with defocused CO₂ laser can have a therapeutic effect on equine injuries, but the mechanisms involved are unclear. A recent study has shown that laser causes an increase in equine superficial tissue temperature, which may result in an increase in blood perfusion and a stimulating effect on tissue regeneration. However, no studies have described the effects on equine tissue perfusion. The aim of the present study was to investigate the effect of defocused CO₂ laser on blood perfusion and to correlate it with temperature in skin and underlying muscle in anaesthetized horses. Differences between clipped and unclipped haircoat were also assessed. Eight horses and two controls received CO₂ laser treatment (91 J/cm²) in a randomised order, on a clipped and unclipped area of the hamstring muscles, respectively. The significant increase in clipped skin perfusion and temperature was on average 146.3 ± 33.4 perfusion units (334%) and 5.5 ± 1.5°C, respectively. The significant increase in perfusion and temperature in unclipped skin were 80.6 ± 20.4 perfusion units (264%) and 4.8 ± 1.4°C. No significant changes were seen in muscle perfusion or temperature. In conclusion, treatment with defocused CO₂ laser causes a significant increase in skin perfusion, which is correlated to an increase in skin temperature.

Effects of haemorrhagic hypotension on the subcapsular artery and microvasculature of the rat testis

Developing germ cells may be sensitive to even moderate reductions in blood flow. Surprisingly, however, experimental evidence suggests that the rat testis may be unable to maintain its blood flow during a decrease in systemic blood pressure. This study was therefore performed in order to answer the following questions: Is the testis able to maintain its blood flow during moderate to major reductions in blood pressure and, if so, at which level of the testicular vasculature (main artery or microcirculation) does this compensatory response take place? Moderate (-20%) and major (-40%) reductions in blood pressure were induced in anaesthetized rats by haemorrhage and the effects on testicular microvascular blood flow and subcapsular testicular artery diameter were examined by using laser Doppler flowmetry and in vivo video-microscopy respectively. Haemorrhagic hypotension led to decreased local testicular blood flow, but the relative reductions in flow were generally only half as large as the reductions in blood pressure. Hypotension also decreased the diameter of the main subcapsular testicular artery. During large reductions in blood pressure the subcapsular testicular artery constricts and testicular blood flow decreases. However, blood flow is reduced proportionally less than the mean arterial pressure, suggesting that local regulatory mechanisms are present in the testicular microvasculature, which may prevent blood flow from falling below a critical level.

Androgens induce CD-9 in human prostate tissue

Based on microarray analyses of LNCaP and LNCaP-r prostatic cell-lines we tentatively identified CD-9 as an androgen sensitive protein. This prompted us to characterize the androgen sensitivity and the correlation to malignancy of CD-9 at the protein level. Using Western blot, RT-PCR and immunohistochemistry the expression of CD-9 was analysed in LNCaP cells stimulated during increasing time by the synthetic androgen R1881 and also in 88 specimens of human prostate cancer tissues. Expression of CD-9 was induced by R1881 in LNCaP. CD-9 was immunolocalized in human prostate tissue sections representing non-malignant tissue as well as tumour areas. In non-malignant glands CD-9 immunoreactivity was observed at the apical and lateral cell borders of luminal epithelial cells. Basal epithelial cells were largely unstained. In tumour areas CD-9 staining intensity was variable and apparently not related to primary Gleason grade. In prostate tissue from a patient under androgen ablation therapy no staining was observed in luminal epithelial cells or in the tumour areas, but some staining was observed in basal epithelial cells. CD-9 is regulated by androgens in LNCaP and present in human prostate specimens. The expression is variable and changes in expression levels. These and earlier studies using other tissues indicate that CD-9 and its cellular localization could have an important role in prostate cancer cell development.

The tyrosine kinase inhibitor ZD6474 inhibits tumour growth in an intracerebral rat glioma model

Malignant glioma is characterised by extensive neovascularisation, principally influenced by vascular endothelial growth factor (VEGF). ZD6474 is a potent inhibitor of VEGF-R2 tyrosine kinase activity, but with additional inhibitory effects on other growth factors. In this study, we have investigated the effects of ZD6474 with regard to tumour growth, neovascularisation, proliferation and apoptosis in the intracerebral rat glioma model, BT4C. ZD6474 (50 and 100 mg kg(-1)) was given as a daily oral gavage. Animals were killed on day 19 and tumour volume was measured. Sections were stained for factor VIII, Ki-67 and for apoptosis. The ability of ZD6474 to inhibit cell growth directly was examined in vitro, using the glioma cell line BT4C and the transformed rat brain endothelial cell line RBE4. Cell growth was analysed with fluorometric microculture cytotoxicity assay to quantify the cytotoxic effects. ZD6474 significantly decreased tumour volume compared to controls. Microvascular density increased after treatment with ZD6474, and tumour cell proliferation index was reduced. There was also an increase in tumour cell apoptosis. In vitro, the growth of both cell lines was significantly reduced. The results reported justify further experimental investigations concerning the effects of ZD6474 in malignant glioma alone or in combination with other modalities.

Expression of vascular endothelial growth factor protein in human renal cell carcinoma

OBJECTIVE

To evaluate the effect of vascular endothelial growth factor (VEGF, one of the most important angiogenetic factors) in renal cell carcinoma (RCC) by analysing many RCCs for the expression of immunohistochemical (IHC) VEGF-staining related to clinicopathological findings and survival.

PATIENTS AND METHODS

VEGF immunostaining was examined with the tissue microarray (TMA) method on tumour samples from 229 patients and validated in 71 by ordinary tissue sections (TS). IHC VEGF expression was quantified by estimating the volume density and staining intensity on a three-grade scale.

RESULTS

In most RCCs there was VEGF staining in the cell cytoplasm and membrane. In cell membranes the VEGF expression declined with storage time. IHC VEGF expression analysed by TMA and TS gave corresponding results. There was no difference in VEGF expression among conventional, papillary and chromophobe RCCs. There were significant correlations between VEGF expression and tumour size and stage. In univariate analysis VEGF expression correlated with survival, especially in conventional RCCs; this prognostic information was lost in multivariate analysis. The VEGF staining intensity correlated only with VEGF expression but not with any clinicopathological factors.

CONCLUSIONS

VEGF protein was present in most RCC cells. There was no difference in VEGF expression among the different RCC types. The correlation between VEGF expression and tumour stage and with prognosis indicates the significance of VEGF within tumour growth and progression in RCC.

Randomised controlled short-term intervention pilot study on rye bran bread in prostate cancer

The short-term effects of rye bran bread intake in prostate cancer were investigated. Ten men with conservatively treated prostate cancer were randomised to a daily supplement of 295 g of rye bran bread and eight men to 275 g of wheat bread (control) with similar fibre content for three weeks. Blood samples, ultrasound-guided core biopsies of the prostate, and urine samples were taken. In the rye group, there was a significant increase in plasma enterolactone, and the apoptotic index increased significantly from 2.1% (SD 1.3) to 5.9% (SD 1.8), P<0.005 as measured by a TUNEL index in four cases in the rye group and seven cases in the control group. Besides a significant decrease in weight in both groups, only small changes were observed in plasma concentrations of prostate specific antigen (PSA), circulating sex hormones, excreted oestrogens, insulin-like growth factor (IGF)-I, and in the endothelial fibrinolytical system. High intake of rye bran bread is suggested to increase apoptosis in prostate tumours.

The clinical implications of the difference between castration, gonadotrophin releasing-hormone (GnRH) antagonists and agonist treatment on the morphology and expression of GnRH receptors in the rat ventral prostate

OBJECTIVE

To examine the effects of castration and continuous gonadotrophin releasing-hormone (GnRH) agonist and antagonist therapy on the expression of GnRH-receptors type I (GnRH-RI) in rat ventral prostate (VP) and pituitary tissue, and to compare the effects on prostate morphology.

MATERIAL AND METHODS

Mature Sprague-Dawley rats were assigned to four treatment groups: group 1, vehicle only; group 2, GnRH agonist goserelin (100 microg/rat/day); group 3, GnRH antagonist cetrorelix (100 microg/rat/day); and group 4, orchidectomy. After 4 weeks the body weights were recorded and VP and pituitary tissue analysed for GnRH-RI expression using a competitive reverse transcriptase-polymerase chain reaction and immunohistochemistry.

RESULTS

GnRH antagonist and orchidectomy decreased testosterone secretion and VP volume similarly, but the effects were not identical. The involution of the glandular lumina was more pronounced after orchidectomy while the antagonist therapy was more effective in suppressing epithelial cell proliferation. In the VP, GnRH-RI mRNA levels were increased after GnRH analogue therapy, but were unaffected by orchidectomy. In the pituitary, GnRH-RI mRNA expression was higher in response to orchidectomy and decreased after GnRH analogue treatment.

CONCLUSION

Treatment with a GnRH antagonist for 4 weeks is more effective than an agonist in suppressing testosterone and inducing VP involution. The GnRH antagonist was more effective in suppressing VP epithelial cell proliferation than was castration, suggesting that it induces reduced proliferation by interfering with effects of locally produced GnRH. These results suggest that different regulatory mechanisms may operate in the rat VP than in the pituitary to control GnRH-RI mRNA expression.

Transrectal core biopsy trauma may increase cell proliferation in prostate tumors

Whilst analyzing the morphological effects of a 3-week dietary intervention in patients with prostate cancer, we made an unexpected observation to the effect that prostate biopsy trauma may, at least transiently, increase prostate tumor cell proliferation. Further studies are needed to evaluate the clinical significance of this observation.

Effects of finasteride on vascular endothelial growth factor

OBJECTIVE

Finasteride has been shown to reduce prostate bleeding in patients with benign prostatic hyperplasia (BPH). The mechanisms behind this are not known, but it has been suggested that finasteride reduces bleeding by inhibiting angiogenesis in the prostate. Studies in animals have shown that castration rapidly induces involution of the prostate vasculature, and androgen-stimulated prostate growth may be angiogenesis dependent. The objective of this study was to explore the response to finasteride on the vasculature and the expression of vascular endothelial growth factor (VEGF), a potent regulatory factor of angiogenesis in human prostate tissue.

MATERIAL AND METHODS

Patients with BPH were randomly assigned to 3 months of treatment either with finasteride (5 mg/day) or placebo before undergoing transurethral resection of the prostate (TURP). Prostate tissue VEGF expression was quantified by Western blot and the vascular density determined in Factor VIII immunostained tissue sections. Serum concentrations of VEGF were measured with ELISA technique.

RESULTS

Patients treated with finasteride (n = 15) showed a decrease in prostate tissue VEGF(165) expression compared with placebo (n = 13) treated patients (p < 0.05), but the vascular density and the serum VEGF levels were unaffected.

CONCLUSIONS

This study shows that finasteride treatment decreases VEGF expression in the human prostate.

Prognostic value of the Gleason score in prostate cancer

OBJECTIVE

To investigate the prognostic value of the Gleason score in prostate cancer.

PATIENTS AND METHODS

A consecutive series of 305 men with prostate cancer diagnosed at transurethral resection (1975-1990) and with no curative treatment was analysed. There was no assessment of prostate-specific antigen level during this period. The mean (range) age at diagnosis was 73.7 (52-95) years and the mean follow-up was 6.4 (0-22) years. The influence of Gleason score and the percentage of the specimen area with tumour (% cancer) on disease-specific survival were assessed using Kaplan-Meier analyses.

RESULTS

Of 305 cancers, 22% had a Gleason score of 4-5, 29% of 6, 18% of 7 and 32% of 8-10. At the follow-up, 89% of the men had died, of whom 42% had died from prostate cancer. The disease-specific 10-year survival was 56%. The disease-specific mean survival (DSMS) for Gleason score 4-5, 6, 7 and 8-10 was 20, 16, 10 and 5 years, respectively (P < 0.001). The DSMS did not differ significantly between Gleason 4 and 5 or between 8-10. There was a trend towards shorter survival for Gleason 4 + 3=7 (DSMS 9 years) than GS 3 + 4=7 (DSMS 13 years; P = 0.16). Gleason score and % cancer were independent predictors of DSMS (P < 0.001).

CONCLUSION

The long-term prognosis of prostate cancer on deferred treatment is predicted well by the Gleason score. Four prognostic categories of prostate cancer are suggested, i.e. Gleason score 4-5, 6, 7 and 8-10.

Blood vessels are regulators of growth, diagnostic markers and therapeutic targets in prostate cancer

The vasculature plays an important role in the normal and malignant prostate. Under basal conditions both glandular epithelial and stromal prostate cells produce an abundance of blood flow and angiogenesis regulating substances and the expression of these is generally increased in prostate tumors. The proportion of proliferating endothelial cells is high in the normal prostate compared to other tissues in the body. After castration effects on the vasculature, such as decreased blood flow and vascular regression, precede effects on the glandular compartment. Correspondingly, hormone induced prostate growth is characterized by early effects on the vasculature such as increased blood flow and endothelial cell proliferation, thus indicating that the vasculature may be involved in the androgenic regulation of the prostate. Prostatic intraepithelial neoplasia (PIN) and prostate cancer are associated with increased vascular density and in experimental models prostate cancer growth is apparently angiogenesis-dependent since tumor growth and progression can be inhibited by antiangiogenic treatment. Moreover, vascular density has been related to prognosis in prostate cancer patients. A better understanding of the pathways regulating angiogenesis in the normal prostate and how these pathways change during malignant transformation can hopefully lead to better prognostic markers and therapies for the large group of patients with prostate cancer. The purpose of this review is therefore to summarize the current knowledge on the role and regulation of the vasculature in the prostate and its potential clinical applications.

Vascular endothelial growth factor-A and -C protein up-regulation and early angiogenesis in a rat photothrombotic ring stroke model with spontaneous reperfusion

This study explored the temporal expression pattern of two subtypes of vascular endothelial growth factor (VEGF) proteins and three subforms of their receptors as well as endothelial proliferation in adult rats subjected to photothrombotic ring stroke with spontaneous reperfusion in the cortical region at risk. The exposed crania of halothane-anesthetized, temperature- and blood gas-controlled male Wistar rats were irradiated with a ring laser beam started simultaneously with systemic injection of the photosensitizer erythrosin B. Rats were repeatedly injected with 5-bromodeoxyuridine (BrdU) after stroke induction. Immunohistochemistry of coronal brain sections showed that VEGF protein subtype C increased simultaneously with subtype A in the ring lesion region at 2 h after irradiation. In the cortical region at risk (i.e., the penumbra-like zone), increased VEGF-C and VEGF-A immunostaining was seen at 24 h with sustained appearance up to 72 h after ischemic onset. Correspondingly, the VEGF-C-specific receptor flt-4 and the VEGF-A receptors flt-1 and flk-1 were up-regulated in a temporal sequence similar to that of their agonist proteins in the cortical ring lesion and the region at risk. At 48 h after stroke induction, proliferating BrdU-immunopositive endothelial cells formed microvessels in the post-ischemic cortical region at risk. These vessels became more pronounced at 72 h and were still visible at 100 days after the stroke. This study suggests that VEGF-C and its receptor flt-4 may cooperate with VEGF-A and its receptors flt-1 and flk-1 to promote early angiogenesis after stroke, which may in turn contribute to spontaneous reperfusion in this focal thromboembolic stroke model.

Didecyl squarate--a practical amino-reactive cross-linking reagent for neoglycoconjugate synthesis

The present paper describes the synthesis and use of the hydrophobic squaric decyl ester glycosides in neoglycoconjugate chemistry. The 2-aminoethyl glycosides of alpha-D-mannopyranose, lactose, globotriose, globotetraose, GM3, and sialyl Lewis(x), as well as the 2-(2-aminoethylthio)ethyl glycoside of alpha-D-mannopyranose, beta-D-glucopyranose, and galabiose were reacted with squaric acid didecyl ester to afford the hydrophobic squaric decyl ester glycosides. These glycosides were efficient reagents for the conjugation to amino-functional microtiter plates, BSA and aminated Sepharose EAH 4B. The decyl ester moiety of the squaric decyl ester glycosides constitutes a traceless hydrophobic tag, which has the major advantage, as compared to the corresponding ethyl esters, that it enables easy purification of the glycosides with silica chromatography and that unreacted excesses glycosides from conjugation reaction mixtures can easily be recovered by means of C18 solid phase extraction.

Castration-induced reduction of vascular endothelial growth factor expression in benign human prostate tissue is lost in advanced prostate cancer

OBJECTIVE

To determine the role of vascular response in the castration-induced regression of benign and malignant human prostate tissue, as recent studies show that castration rapidly decreases blood flow and induces endothelial cell death, which may be important for subsequent epithelial cell death and involution of the glandular tissue of the prostate.

MATERIALS AND METHODS

The expression of vascular endothelial growth factor (VEGF) and its receptors was analysed using the quantitative reverse transcriptase-polymerase chain reaction, in benign and tumour areas of core biopsies taken before, and approximately 1 week after castration therapy. The castration-induced VEGF response was related to therapy-induced changes in tumour cell apoptotic index and subsequent response in serum prostate-specific antigen (PSA). In another set of patients, serum VEGF was quantified by enzyme-linked immunosorbent assay before, and at 3--6 months after castration therapy.

RESULTS

VEGF mRNA was down-regulated after castration in benign prostate tissue (P < or = 0.05), whereas in tumour tissue, VEGF levels were reduced in some of the patients but unchanged or increased in others. In most patients whose tumour tissue responded with VEGF reduction, there was a corresponding increase in tumour cell apoptosis. Serum VEGF levels were not significantly changed after castration. Almost all patients responded with a substantial reduction in serum PSA after castration.

CONCLUSION

Castration reduces VEGF mRNA expression in benign prostate tissue and generally in those prostate tumours where castration also induces tumour cell apoptosis. This suggests that a therapy-induced down-regulation of VEGF could be important for tumour cell death.

Radioimmunoscintigraphy using an anti-prostate monoclonal antibody (E4): a dosimetric evaluation

The aim of this study was to evaluate different strategies to increase the tumour radiation dose for experimental radioimmunotherapy using 125I-labelled monoclonal antibody (MAb) E4 in a nude mice model xenografted with DU-145 tumours. The effects from a single injection of the 125I-labelled MAb E4, the same total amount of radiolabelled MAb E4 divided into three repeated injections, and the effect of pre-targeting with non-labelled MAb E4 for reducing the amount of shed antigen were investigated. Based on repetitive quantitative radioimmunoscintigraphies, calculation of the tumour radiation dose delivered from the 125I-nuclide was performed for each strategy. The single injection strategy without pretargeting rendered the highest mean tumour radiation dose, i.e. 0.23 Gy/MBq. Pretargeting with non-labelled MAb E4 before a single injection of [125I]E4 resulted in a slightly lower mean tumour radiation dose, i.e. 0.19 Gy/MBq, compared to the single injection alone. An even lower mean tumour radiation dose, i.e. 0.14 Gy/MBq, was obtained when the same total administered amount of activity was divided into three separate injections given in 10-day intervals. We concluded that the single injection strategy is the most efficient when using MAb E4 in this tumour model. The tumour radiation doses were not increased by dividing the same amount of activity into three injections or by pretargeting with non-labelled MAb E4.

Gonadotropin-releasing hormone receptor expression in the human prostate

BACKGROUND

Inhibitory effects of gonadotropin-releasing hormone (GnRH) analogs on prostate cancer cell proliferation, both in vivo and in vitro, indicate the presence of specific binding sites for GnRH on prostate cancer cells. To investigate this issue further, we examined the expression of GnRH receptor (GnRH-R) mRNA and protein in human prostate biopsies as well as in other extrapituitary tissues.

METHODS

The relative quantity of GnRH-R mRNA was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) in human prostate biopsies. Extrapituitary GnRH-R levels were determined by a semiquantitative PCR reaction.

RESULTS

Using PCR, a relatively high expression level of GnRH-R mRNA was found in prostate tumor tissue followed by normal prostate, thymus, and kidney expression levels. The levels showed by heart, brain, placenta, lung, liver, skeletal muscle, pancreas, colon, ovary, small intestine, spleen, and testis were low but detectable, whereas peripheral blood leukocyte showed no demonstrable product. GnRH-R immunoreactivity was localized in both luminal and basal epithelial cells in benign and malignant prostate tissue, and GnRH-R were also observed in intraprostatic lymphocytes. The relative GnRH-R mRNA levels in prostate biopsies from 16 patients showed a wide range of individual differences, but these differences were not related to histological grade. Castration therapy did not significantly influence GnRH-R mRNA expression in normal and malignant prostate tissue.

CONCLUSIONS

These results suggest that epithelial cells and infiltrating lymphocytes are targets for GnRH action in the human prostate. Comparative data show relatively high GnRH-R expression in human prostate tissue compared to other human tissues.

Plasma prolactin and prostate cancer risk: A prospective study

Prolactin, a pituitary peptide hormone with multiple effects, stimulates prostate growth in experimental models. In humans, prolactin receptors are present in the prostate and are particularly abundant in pre-cancerous lesions. This suggests that prolactin could also be involved in the development of prostate cancer. In this study, we tested the hypothesis that elevated levels of circulating prolactin are associated with an increase in prostate cancer risk. We conducted a case-control study nested within the Northern Sweden Health and Disease Cohort using plasma samples collected from 29,560 men at a health survey. We measured prolactin in plasma from 144 men who had a diagnosis of prostate cancer after a median follow-up time of 4 years after health survey and from 289 controls matched for age and date of recruitment. Risk was not associated with plasma prolactin levels in univariate regression analysis. Odds ratios of prostate cancer for increasing quartiles of prolactin were 1.0, 0.92 (95% CI 0.51-1.65), 0.82 (0.45-1.51) and 0.85 (0.49-1.47). Relative risk estimates remained unchanged after adjustments for height and weight or for plasma levels of testosterone, sex hormone-binding globulin, IGF-I and IGF-binding protein-3. Elevated circulating levels of prolactin were not related to an increase in prostate cancer risk, indicating that high circulating prolactin is not associated with development of prostate cancer.

Microvascular testicular blood flow as evaluated by laser Doppler flowmetry after the surgical induction of varicocele

This study was conducted to evaluate the changes in microvascular testicular blood flow (microvascular TBF), which may be associated with varicocele. The pathology was developed through partial ligation of left renal vein in 4 groups of rats. Controls of each group underwent sham surgery. It was observed that microvascular TBF dropped and its vasomotion became inhibited once the left renal vein was partially ligated as studied by laser Doppler flowmetry (LDF). Four to five minutes later, blood flow rose to the pretreatment level and that of controls. Vasomotion reappeared with a uniform frequency and amplitude. At different periods of varicocele bearing (1, 3, 6, and 14 weeks) microvascular TBF was reevaluated. Vasomotion appeared intact without any abnormalities in the 4 groups. To examine the response of testicular microvasculature after surgical creation of the varicocele to pharmacological stimulation another group of animals received human chorionic gonadotropin (hCG) treatment 6 weeks after varicocele creation. Vasomotion was inhibited in these animals. In conclusion, LDF is a suitable tool to evaluate microvascular TBF in vivo. It can detect acute changes in blood flow that may happen at surgical induction of varicocele. In addition, the vasculature of the testis with a surgically induced varicocele can still respond to hCG stimulation.

BRCA2 mutation in a family with hereditary prostate cancer

Hereditary prostate cancer is a genetically heterogeneous disease, and so far four different susceptibility loci have been identified. Reports of associated cancers are few, and it is generally considered a site-specific disease. However, some reports have shown an elevated risk for prostate cancer among BRCA2 mutation carriers. In this report, we present a family in which the father and four of his sons were diagnosed with prostate cancer at exceptionally early ages (51, 52, 56, 58, and 63 years, respectively). In addition, three daughters were diagnosed with breast cancer between the ages of 47 and 61. In this family, a truncating mutation in exon 11, 6051delA of the BRCA2 gene, leading to an early termination of the protein (codon 1962), was identified. Although BRCA2 is probably responsible only for a very small fraction of hereditary prostate cancers, this finding supports previous reports of an increased risk of prostate cancer in BRCA2 mutation carriers.

Leptin is associated with increased prostate cancer risk: a nested case-referent study

A Western lifestyle has been implicated in the pathogenesis of prostate cancer. However, no clear association between obesity and prostate cancer has been shown. Leptin may stimulate prostate growth and angiogenesis, and receptors for leptin are present in the prostate. Leptin may, thus, be associated with increased risk of prostate cancer. One hundred forty-nine men with prostate cancer were identified (together with 298 matched referents) who, before diagnosis, had participated in population-based health surveys in Northern Sweden. Blood pressure, body mass index, and use of tobacco were recorded. Leptin, insulin, insulin-like growth factor I (IGF-I), IGF-I-binding proteins 1-3, testosterone, and sex hormone-binding globulin were analyzed in stored samples. Their influences on prostate cancer were estimated by conditional logistic regression analysis. Prostate cancer specimens were investigated for immunoreactivity for the leptin receptor. Relative risk (95% confidence intervals) estimates of prostate cancer over the quintiles of leptin were 1.0, 2.1 (1.1-4.1), 2.6 (1.4-4.8), 1.4 (0.7-2.7), and 1.6 (0.8-3.2). Adjustments for metabolic variables, testosterone, and IGF-I and its binding proteins did not attenuate this increased risk. Immunoreactivity for the leptin receptor was detected in normal, high-grade prostatic intraepithelial neoplasia lesions and malignant prostatic epithelium. Moderately elevated plasma leptin concentrations are associated with later development of prostate cancer. This may be due to direct effects of leptin on prostatic intraepithelial neoplasia lesions, or to indirect actions through other mechanisms. A critical fat mass related to an interior milieu favorable for prostate cancer development seems to exist, because intermediate but not high leptin levels are related to prostate cancer risk.

Low frequency of microsatellite instability in hereditary prostate cancer

OBJECTIVE

To investigate whether there is widespread microsatellite instability (MSI) in families with hereditary prostate cancer (HPC).

PATIENTS AND METHODS

Eighty-four prostate tumours from 80 Swedish men in 35 families with HPC were screened for genetic instability at microsatellite marker loci BAT-25, BAT-26, BAT-34C4, D2S123 and D17S250.

RESULTS

MSI was detected in only five individuals from different families. Three tumours (4%) were unstable at more than two MSI loci and hence classified as high-frequency MSI (MSI-H) according to a previous definition. Interestingly, two of the MSI-H tumours were from patients in families with both HPC and familial colon cancer.

CONCLUSIONS

Widespread MSI is a rare event in hereditary prostate cancer, indicating that defective DNA mismatch repair is not an important element in the genesis of HPC.

Role of transforming growth factor-beta1 in prostate cancer

TGF-beta1 is an important regulator of the normal and malignant prostate. In the non-malignant prostate, TGF-beta1 stimulates cell differentiation, inhibits epithelial cell proliferation, and induces epithelial cell death. TGF-beta1 is secreted into semen where it is an important immunosuppressive factor. Prostate cancer cells express high levels of TGF-beta1, which seems to enhance prostate cancer growth and metastasis by stimulating angiogenesis and by inhibiting immune responses directed against tumour cells. Prostate cancer cells frequently lose their TGF-beta receptors and acquire resistance to the anti-proliferative and pro-apoptotic effects of TGF-beta1. Accordingly, high expression of TGF-beta1 and loss of TGF-beta receptor expression have been associated with a particularly bad prognosis in human prostate cancer patients. TGF-beta1 also seems to be a mediator of castration-induced apoptosis in androgen dependent normal and malignant prostate epithelial cells. The ability of some prostate tumours to avoid castration-induced apoptosis may not, however, be simply due to loss of TGF-beta receptor type I or type II expression in the tumour cells. It may also be related to an inability of these cells to up-regulate TGF-beta receptor levels in response to castration or possibly due to defects downstream of the receptors. Short-term therapy-induced changes in the TGF-beta system in prostate tumours can probably be used to predict the long-term response to androgen ablation treatment. Further investigations into the TGF-beta system in the prostate are needed, however, to elucidate how alterations in this system affect the behaviour of prostate tumours, and whether this system can be manipulated for therapeutical purposes.

Effects of acute graded reductions in testicular blood flow on testicular morphology in the adult rat

The effect of moderate reductions in testicular blood flow has not been studied systematically. The aim of this study was, therefore, to examine the effects of different degrees of blood flow reduction on testicular morphology and to determine how much flow can be reduced before damage occurs. The subcapsular testicular artery was partially ligated in the left testes of adult rats. Testicular blood flow was measured before, immediately after, and 5 h after the ligation using laser Doppler flowmetry. After 5 h of partial ligation, the testes were removed, and their morphology was examined and related to the degree of blood flow reduction. The number of in situ end-labeled- or TUNEL-positive (i.e., dying) germ cells and the volume density of intravascular polymorphonuclear (PMN) leukocytes were measured. When flow was reduced to approximately 70% or less of its pretreatment value, a dose-related increase in the number of dying spermatogonia and early spermatocytes was seen. The PMN leukocytes accumulated in testicular blood vessels after partial ligation, and the maximum number was observed in testes where flow was reduced by approximately 50% of the pretreatment value. In conclusion, early stages of spermatogenesis are sensitive to a moderate, acute reduction in blood flow. Discrete reductions in flow may, therefore, have a large impact on sperm production.

Low frequency of allelic imbalance at the prostate cancer susceptibility loci HPC1 and 1p36 in Swedish men with hereditary prostate cancer

The aim of this study was to investigate allelic imbalance at the major human prostate cancer susceptibility locus HPC1 at 1q24-25 and the recently reported, putative, susceptibility locus at 1p36 in prostate tumors from Swedish families with hereditary prostate cancer. We analyzed 31 prostate tumors and two lymph node metastases from 33 Swedish men in 22 families with hereditary prostate cancer for the presence of allelic imbalance using microsatellite markers D1S158, D1S422, and D1S238 for the HPC1 locus and D1S1597, D1S407, and D1S489 for the 1p36 locus. Frequencies of allelic imbalance at the two investigated loci were quite low, 3 of 27 informative tumors at the 1p36 locus and 3 of 27 informative tumors at the HPC1 locus. Interestingly, two tumors showed allelic imbalance at both loci investigated, suggesting that they may have lost a great part of chromosome 1. Taking this possibility into consideration, the specific loss of the two investigated loci may be even lower (1 of 27 informative tumors for either locus). The very low level of allelic imbalance found at HPC1 and 1p36 makes it unlikely that these loci encode genes that are acting as classic tumor suppressor genes in the initiation or progression of hereditary prostate cancer. Of the eight tumors from HPC1-linked families, only two showed AI at the HPC1 locus, one of which had lost the wild-type allele.