Real-time non-rigid target tracking for ultrasound-guided clinical interventions.

Biological motion is a problem for non- or mini-invasive interventions when conducted in mobile/deformable organs due to the targeted pathology moving/deforming with the organ. This may lead to high miss rates and/or incomplete treatment of the pathology. Therefore, real-time tracking of the target anatomy during the intervention would be beneficial for such applications. Since the aforementioned interventions are often conducted under B-mode ultrasound (US) guidance, target tracking can be achieved via image registration, by comparing the acquired US images to a separate image established as positional reference. However, such US images are intrinsically altered by speckle noise, introducing incoherent gray-level intensity variations. This may prove problematic for existing intensity-based registration methods. In the current study we address US-based target tracking by employing the recently proposed EVolution registration algorithm. The method is, by construction, robust to transient gray-level intensities. Instead of directly matching image intensities, EVolution aligns similar contrast patterns in the images. Moreover, the displacement is computed by evaluating a matching criterion for image sub-regions rather than on a point-by-point basis, which typically provides more robust motion estimates. However, unlike similar previously published approaches, which assume rigid displacements in the image sub-regions, the EVolution algorithm integrates the matching criterion in a global functional, allowing the estimation of an elastic dense deformation. The approach was validated for soft tissue tracking under free-breathing conditions on the abdomen of seven healthy volunteers. Contact echography was performed on all volunteers, while three of the volunteers also underwent standoff echography. Each of the two modalities is predominantly specific to a particular type of non- or mini-invasive clinical intervention. The method demonstrated on average an accuracy of ∼1.5 mm and submillimeter precision. This, together with a computational performance of 20 images per second make the proposed method an attractive solution for real-time target tracking during US-guided clinical interventions.

Evaluation of a novel therapeutic focused ultrasound transducer based on Fermat's spiral.

The purpose of this study was to evaluate a novel phased array transducer design rule for therapeutic focused ultrasound applications. This design rule uses the discretized Fermat's spiral to determine the positioning of the transducer elements for a given number of elements and f-number. Using this principle, three variations of Fermat's spiral were generated, aimed at (1) grating lobe minimization, (2) side lobe minimization, and (3) an optimized element packing efficiency. For each spiral, sparse layouts using identical circular elements and fully populated layouts based on additional Voronoi tessellation were evaluated numerically. Evaluation criteria included the element size distribution, beam steering capabilities, focal plane pressure distribution, prefocal pressure distribution, and practical considerations. Finally, one Voronoi-tessellated design with a focal length and aperture diameter of 16 cm and a natural frequency of 1.3 MHz was evaluated experimentally through hydrophone measurements. The numerical evaluation showed that while sparse arrays possess superior beam steering capabilities for a given number of elements, the focal point quality and prefocal pressure distribution is substantially more favorable when using the Voronoi-tessellated designs. Beam steering was shown to be feasible with the tessellated designs for lateral deflections up to 10 mm and axial deflections up to 20 mm. The experimental evaluation showed that such a transducer is capable of inducing 40.00 MPa rarefactional and 237.50 MPa compressional peak pressure levels at 800 W instantaneous acoustic output power under free-field conditions, making the system potentially relevant for thermal ablation therapy, histotripsy applications, and shockwave-enhanced heating.

Increasing the HIFU ablation rate through an MRI-guided sonication strategy using shock waves: feasibility in the in vivo porcine liver.

This study investigated whether an MR-guided pulsed HIFU ablation strategy could be implemented under clinical conditions, using a transducer designed for uterine fibroid ablation, to obtain an ablation rate that is sufficiently high for clinical abdominal HIFU therapy in highly perfused organs. A pulsed HIFU ablation strategy, aimed at increasing the energy absorption in the HIFU focal area by local shock wave formation in the non-linear pressure regime, was compared to an energy-equivalent continuous wave sonication strategy in the linear pressure regime. Both ablation strategies were used for transcutaneous sonication of pre-defined treatment cells in the livers of 5 pigs in vivo. Temperature evolution in both the target area as well as the pre-focal muscle layer was monitored simultaneously using MR thermometry. Local energy absorption and thermal dose volumes were shown to be increased using the pulsed ablation strategy, while preserving healthy tissue in the near field of the acoustic beam. Respiratory motion compensation of both acoustic energy delivery and MR thermometry was applied through gating based on MR navigator echoes. Histopathology showed that confluent vacuolated thermal lesions were created when the pulsed ablation strategy was used. Additionally, it was shown that the heat sink effect caused by the presence of larger vessels could be overcome. The pulsed HIFU ablation strategy achieved an ablation rate of approximately 4 ml per hour in the in vivo porcine liver, without causing undesired damage to healthy tissues in the near field.

Outcome of 12 antenatally diagnosed fetal arachnoid cysts: case series and review of the literature.

OBJECTIVES: To investigate the natural history, associated abnormalities and outcome of 12 fetuses with arachnoid cyst diagnosed antenatally by ultrasound and magnetic resonance imaging and to compare the outcome with cases in the literature. METHODS: A retrospective study of all cases of antenatally detected fetal arachnoid cysts was performed in patients referred to a tertiary unit between 2007 and 2013. Associated abnormalities, pregnancy outcome and postnatal follow-up were analyzed. All papers about prenatally diagnosed arachnoid cysts, of the last 30 years, were evaluated (search terms in Pubmed: "prenatal diagnosis", "Arachnoid Cysts"). RESULTS: Fetal arachnoid cysts were diagnosed in 12 fetuses, 9 were females. The mean gestational age of diagnosis was 28 1/7 (range 19 1/7-34 2/7 weeks). A total of 9 cases were supratentorial, 3 were located in the posterior fossa. In 10 cases a fetal MRI was performed which confirmed brain compression in 4 out of 5 supratentorial arachnoid cyst. MRI did not reveal other malformations nor signs of nodular heterotopia. Only one fetus presented with additional major anomalies (bilateral ventricumomegaly of >20 mm and rhombencephalosynapsis) leading to a termination of pregnancy. Two neonates underwent endoscopic fenestration of the arachnoid cyst in the first week of life with no additional intervention in childhood. All but one (10/11) had a favorable postnatal outcome. This child suffered from visual impairment at autism was diagnosed at the age of 5. One child had a surgical correction of strabismus later in childhood. In one child the infratentorial arachnoid cyst regressed spontaneously on ultrasound and MRI in the postnatal period. CONCLUSIONS: The majority of arachnoid cysts in this series are of benign origin and remain stable. Based on the current series and the review of the literature, in the absence of other associated anomalies and when the karyotype is normal, the postnatal overall and neurological outcome is favorable. Large suprasellar arachnoid cysts however, may cause visual impairment and endocrinological disturbances. Rarely associated cerebral or cerebellar malformations are present. Modern postnatal management of suprasellar arachnoid cyst consists of endoscopic cystoventriculostomy.

Colostrum yield and piglet growth during lactation are related to gilt metabolic and hepatic status prepartum.

It was hypothesized that colostrum production could be influenced by sow peripartum endocrine, metabolic, and hepatic status. The plant extract silymarin was shown to influence endocrine and hepatic status in several species. The aims of the present study were to investigate the effects of silymarin intake during late pregnancy on sow hormonal and hepatic status and to determine whether relations exist between sow hepatic and metabolic status during the peripartum period and colostrum yield and piglet performances during lactation. From d 107 of pregnancy until farrowing, nulliparous sows were either fed 12 g/d of silymarin (SIL; n = 15) or no treatment (Control; n = 12). Piglet BW was recorded directly after birth, 24 h after birth of the first piglet, and at 7, 14, and 21 d of lactation. Blood samples were collected from sows on d 107 and 109 of pregnancy, daily from d 111 of pregnancy until d 2 of lactation, and on d 7 and 21 of lactation. They were assayed for endocrine, metabolic, and hepatic variables. Colostrum yield was estimated during 24 h starting at the onset of farrowing. Silymarin did not influence colostrum yield (3.7 ± 0.3 kg) or gross composition (P > 0.10), nor did it affect serum prolactin concentrations or plasma concentrations of progesterone, estradiol-17ß, or cortisol (P > 0.10). Mean litter BW gain was lower (P < 0.05) during the first week and tended (P < 0.10) to be lower during the second week of lactation in litters from SIL sows. Silymarin had no effect on plasma concentrations of aspartate transaminase, alanine transaminase, γ-glutamyl transferase (γ-GT), alkaline phosphatase, or total cholesterol (P > 0.10). Colostrum yield was positively correlated with urea (r = 0.50; P = 0.01) and creatinine (r = 0.43; P = 0.03) concentrations in sows on the day before farrowing. Mean litter BW gain over 2 wk was negatively correlated with concentrations of ß-hydroxybutyric acid (r = -0.50; P = 0.01) and γ-GT (r = -0.42; P = 0.03) on the day before farrowing and was positively correlated with urea concentrations on the day before farrowing (r = 0.54; P = 0.01). In conclusion, at the dose of 12 g/d, silymarin did not influence prolactin concentrations or the hepatic status of sows, had no impact on colostrum production, and decreased litter BW gain in early lactation. Colostrum yield and litter performance during lactation were correlated with some markers of sow metabolic and hepatic status measured during the prepartum period.

Effects of high fiber intake during late pregnancy on sow physiology, colostrum production, and piglet performance.

Dietary fiber given during pregnancy may influence sow endocrinology and increase piglet BW gain during early lactation. The aim of the current study was to determine whether dietary fiber given to sows during late pregnancy induces endocrine changes that could modulate sow colostrum production and, thus, piglet performance. From d 106 of pregnancy until parturition, 29 Landrace×Large White nulliparous sows were fed gestation diets containing 23.4 [high fiber (HF); n=15] or 13.3% total dietary fiber [low fiber (LF); n=14]. In the HF diet, wheat and barley were partly replaced by soybean hulls, wheat bran, sunflower meal (undecorticated), and sugar beet pulp. After parturition, sows were fed a standard lactation diet. Colostrum production was estimated during 24 h, starting at the onset of parturition (T0) and ending at 24 h after parturition (T24) based on piglet weight gains. Jugular blood samples were collected from sows on d 101 of pregnancy, daily from d 111 of gestation to d 3 of lactation, and then on d 7 and 21 of lactation (d 0 being the day of parturition). Postprandial kinetics of plasma glucose and insulin concentrations were determined on d 112 of pregnancy. The feeding treatment did not influence sow colostrum yield (3.9±0.2 kg) or piglet weight gain during the first day postpartum to d 21 of lactation. Colostrum intake of low birth weight piglets (<900 g) was greater in litters from HF sows than from LF sows (216±24 vs. 137±22 g; P=0.02). Preweaning mortality was lower in HF than LF litters (6.2 vs. 14.7%; P=0.01). Circulating concentrations of progesterone, prolactin, estradiol-17ß, and cortisol were not influenced by the treatment. Sows fed the HF diet had greater postprandial insulin concentrations than LF sows (P=0.02) whereas the postprandial glucose peak was similar. At T24, colostrum produced by HF sows contained 29% more lipid than colostrum produced by LF sows (P=0.04). Immunoglobulin A concentrations in colostrum were lower at T0 and T24 (P=0.02) in HF than LF sows (at T0: 8.6±1.1 vs. 11.9±1.1 mg/mL; at T24: 2.5±0.7 vs. 4.8±0.7 mg/mL). In conclusion, dietary fiber in late pregnancy affected sow colostrum composition but not colostrum yield, increased colostrum intake of low birth weight piglets, and decreased preweaning mortality, but these effects were not related to changes in peripartum concentrations of the main hormones involved in lactogenesis.

Reduced feed intake of lactating primiparous sows is associated with increased insulin resistance during the peripartum period and is not modified through supplementation with dietary tryptophan.

The aim of this experiment was to investigate whether insulin resistance is related to the dietary concentration of Trp and the ADFI of primiparous sows having similar body conditions. Twenty-four primiparous sows were catheterized on d 97 of pregnancy. Blood samples were collected during 3 tests: after the ingestion of 1.5 kg of feed (meal test), after the intravenous infusion of 0.5 g of glucose/kg of BW (glucose tolerance test), and during an euglycemic hyperinsulinemic clamp with an infusion rate of 100 ng of insulin x kg of BW(-1) x min(-1). Both tests were performed at 4 stages at approximately d 103 and 110 of pregnancy and at d 3 and 10 of lactation. Sows were fed a diet containing 0.16 or 0.26% of total Trp (suboptimal vs. slight excessive Trp supply according to recommendations for lactating sows) from d 104 of pregnancy after the first clamp until weaning. The dietary treatment did not result in differences in ADFI, BW, and backfat changes, and growth of piglets during lactation. Plasma Trp concentration was greater for the sows allocated to the slight excessive Trp diet than for the sows allocated to the suboptimal Trp diet (P < 0.05). Plasma glucose, NEFA, and urea profiles during the meal tests were not affected by the dietary treatment. At d 3 of lactation, the insulin concentration at 105 (P = 0.03) and 120 min (P = 0.04) after meal intake was less for the sows allocated to the slight excessive Trp diet than for the sows allocated to the suboptimal Trp diet. On d 10 of lactation, the glucose half life (P = 0.03) and the time needed to reach 25% of the area under the insulin curve (P = 0.04) during the tolerance test were less for the sows allocated to the slight excessive Trp diet than for the sows allocated to the suboptimal Trp diet. The glucose infusion rate during euglycemic hyperinsulinemic clamps was similar in the 2 Trp groups of sows. Irrespective of the dietary treatment, the ADFI of the sows was negatively related to the glucose half life during the glucose tolerance test and positively related to the glucose infusion rate during the clamp (P < 0.05). This relationship observed with the tests performed during early lactation was already found with the tests performed during late pregnancy (P < 0.02). Present findings indicate that a dietary Trp supply of 0.26% does not increase feed intake in lactating primiparous sows. This result indicates that the interest in a Trp supplementation during the peripartum period can be questioned. Irrespective of the dietary treatment, the reasons why sows with similar rearing conditions develop different rates of insulin resistance during pregnancy remain to be elucidated.

Feed intake in the multiparous lactating sow: its relationship with reactivity during gestation and tryptophan status.

Voluntary feed intake in sows after parturition may be related to the capacity of the sow to cope with the numerous changes occurring around farrowing. This experiment was undertaken to investigate whether the feed intake during lactation was related to the reactivity of the sow during gestation and plasma Trp and cortisol concentrations. On d 58 of pregnancy, 37 sows were individually placed in a novel environment, and their behavior was observed during a 5-min open-field test. This test allowed the selection of 12 reactive (R) and 8 nonreactive (NR) sows for the study. Sows were fed 3 kg of a standard gestation diet/d before farrowing and a standard lactation diet ad libitum thereafter. The behavioral reactivity of sows when a human touched their neck in the farrowing crate was evaluated on d 72 of gestation, and their behavior during farrowing was analyzed. Sows were catheterized on d 70 of gestation, and blood samples were taken after an overnight fast on d 37 before farrowing, daily during the week before and the week after parturition, and on d 14 and 21 of lactation for plasma Trp and cortisol determination. The NR sows were less reactive to human contact (P=0.02), had a shorter farrowing duration (P=0.02), and tended to have a shorter birth interval between piglets (P=0.09) than the R sows. Feed intake was greater for the NR sows than for the R sows during wk 1 of lactation (P=0.02), as well as during the whole lactation (P=0.03). Plasma cortisol concentration was maximal on the day after farrowing (P=0.01) and returned to basal concentration within 4 d postpartum. No relationship was observed between sow behavior and plasma concentration of cortisol. For both groups of sows, plasma concentrations of Trp between d 2 and 4 postpartum were less than during gestation (P<0.05). The NR sows had decreased plasma Trp concentrations compared with the R sows during wk 1 of lactation (P=0.02). A low reactivity during gestation was associated with behavior of the sow that was favorable to piglet survival during farrowing, increased feed intake, and decreased plasma Trp concentration during wk 1 of lactation. Further research is needed to elucidate whether Trp or Trp metabolites are related to reactivity and ADFI of the reproducing sow.

[First trimester ultrasound screening for structural and chromosomal anomalies in multiple pregnancy]. / Ultrazvukov skrining za strukturni i khromozomni anomalii pri mnogoplodna bremennost v purvi trimectur.

AIM OF THE STUDY: To assess the feasibility of first trimester ultrasound screening for structural and chromosomal fetal anomalies in multiple gestations. METHODS: An observational prospective follow up study was carried out in 32 cases of multiple pregnancies. Two scans were scheduled in each case--the first, between 6-9 weeks of gestation (w.g.) and the second, between 11-14 w.g. The aim was assessment of fetal number, viability, chorionicity/amnionicity and fetal biometry. In addition, nuchal translucency [NT] measurement, assessment of risk for chromosomal anomalies and fetal anatomy survey were always performed. Increased NT > or = 95 percentile and/or detection of structural anomaly were considered indications for invasive prenatal diagnosis and fetal karyotyping. Selective fetocide was considered in cases of chromosomal or structural anomalies and in high-order multiple gestations (> or = 3 fetuses). Pregnancy outcome was ascertained by the physical examination of the fetuses, placentas and membranes postpartum, the hospital records, the referring physicians or the parents. RESULTS: From 32 cases of multiple pregnancies included in the study, 28 were twins, and 4--triplets. 68% (19/28) of the twin pregnancies were bichorionic-biamniotic [Bi-Bi], 25% (7/28)--monochorionic-biamniotic [Mo-Bi] and 7% (2/28)--monochorionic-monoamniotic [Mo-Mo]. 4 cases of increased NT in one of the twins (1--associated with trisomy 21) were observed, as well as 2 cases of structural fetal anomalies (1--discordant for exencephaly, and 1--with conjoint twins), 2 cases of feto-fetal transfusion syndrome that developed in the second trimester (1--associated with increased NT between 11-14 w.g.), 1 case of TRAP syndrome [twin-reversed arterial perfusion] and 1 case of cord entanglement in monoamniotic twins. In addition, there were 4 cases of a vanishing twin in the first trimester, and in 2 other cases spontaneous miscarriage of both twins occurred before 24 w.g. In two of the triplet pregnancies selective fetocide was performed, one was successfully delivered at 33 w.g. and in the last case the parents chose to terminate the pregnancy. CONCLUSIONS: First trimester ultrasound is a method of choice for detection of major structural fetal anomalies in multiple gestations. Increased NT between 11-14 w.g. in multiple pregnancies is a useful screening tool for detection of chromosomal fetal anomalies, while in monochorionic twins its presence might predict the development of fetofetal transfusion syndrome. First trimester selective fetocide in high-order multiple gestations or in affected twins is one of the options in pregnancy management.

[Ultrasound screening and diagnosis of fetal structural abnormalities between 11-14 gestational weeks]. / Ultrazvukov skrining i diagnostika na strukturnite anomalii na ploda mezhdu 11-14 g.s.

AIM OF THE STUDY: To assess the feasibility of ultrasound screening and diagnosis of structural fetal anomalies at the 11-14 week scan. METHODS: An observational prospective follow up study from March 2000 till May 2003 was performed at three referral centers by seven experienced sonographers with high-resolution ultrasound equipment. 1135 singleton pregnancies between 11+0 and 14+6 weeks gestation (w.g.) participated in the study. The first trimester scan included assessment of fetal number, viability and biometry, nuchal translucency [NT] measurement and fetal anatomy survey performed according to standardized published protocols. Increased NT > or = 95th centile and/or diagnosis of structural fetal anomaly was considered as indication for invasive prenatal diagnosis, early fetal echocardiogram and follow-up scans, including a detailed fetal anomaly scan at 18-22 w.g. and a third scan at 28-32 w.g. Pregnancy outcome was ascertained from hospital records, referring physicians or the patients themselves. RESULTS: The overall prevalence of structural fetal anomalies in the present study was 4.6% (53/1135). 22% (12/53) of the structural anomalies were detected between 11-14 w.g. 9 of those had normal karyotype, and 3 were associated with chromosomal anomalies. Furthermore, 10 cases of increased NT, with or without non-immune hydrops fetalis, were associated with congenital heart disease, rare genetic syndromes and adverse pregnancy outcome later in gestation. The ultrasound detection rate of structural fetal anomalies in the present study increased from 22% (12/53), to 69% (37/53) and 79% (42/53) for the first trimester scan, the first and second trimester scans, and the combination of all three scans, respectively. 21% (11/53) of all structural fetal anomalies were missed by prenatal ultrasound. CONCLUSIONS: The first trimester scan is a method of choice for the diagnosis of major structural fetal anomalies. NT measurement is a useful screening test for chromosomal anomalies. In cases with increased NT subsequent development of congenital heart disease, rare genetic syndromes or adverse pregnancy outcome should be ruled out. At present, the second trimester scan constitutes an indispensable tool for the detection of most structural abnormalities. Even in advanced gestation the prenatal diagnosis of certain anomalies is difficult and often unfeasible.

Primary squamous cell carcinoma of the breast.

Primary squamous cell carcinoma of the breast is a rare neoplasm. We herein report two cases of primary squamous cell carcinoma of the breast, each with a different clinical manifestation. A 75-year-old patient with bilateral breast cancer and a 73-year-old woman with a mastitis carcinomatosa. Histopathology revealed that both tumours were squamous cell carcinomas. In the first case there was a coexisting adenocarcinoma in the contralateral breast. The diagnostic and therapeutic challenges are discussed in a review of the literature. The initial management of primary squamous cell carcinoma should be slightly different to that of more common types of breast cancer.

Second trimester maternal dimeric inhibin-A in the multiple-marker screening test for Down's syndrome.

The aim of this study was to evaluate the additional value of dimeric inhibin-A serum concentration in second trimester multiple-marker screening tests for pregnancies affected by Down's syndrome. We anticipated that second trimester maternal serum dimeric inhibin-A concentrations would be altered in pregnancies complicated by fetal Down's syndrome and that dimeric inhibin-A would perform better than one of the three substances analysed in the multiple-marker screening test currently in use. A total of 1156 serum samples were screened for dimeric inhibin-A in parallel with the routine classic triple test screening programme performed on a random obstetric population. Classic triple test performance was compared with detection rates obtained after substitution of unconjugated oestriol by inhibin-A and with the performance of inhibin-A and alpha-fetoprotein alone. Absolute dimeric inhibin-A maternal serum concentrations of Down's syndrome pregnancies were indeed significantly higher than those of normal pregnancies in our screened population. The performance of dimeric inhibin-A in combination with the multiple-marker screening test, however, is limited because of its strong correlation with intact human chorionic gonadotrophin.

Dimeric inhibin serum values as markers of ovarian activity in pill-free intervals.

Levels of inhibin A and B as well as other hormones in serum samples obtained during the pill-free interval in women taking combined oral contraceptives (OC) were measured to asses the extent of ovarian activity during that period. Type of pill and day of pill-free interval were recorded during routine gynecologic check-ups, if patients were in the pill-free period and had taken their pills regularly in the previous cycle. In addition to inhibin A and B, serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), and progesterone were also quantified. Inhibin B levels rise significantly in parallel with rising levels of FSH, LH, and E2. Progesterone levels were completely suppressed and inhibin A levels rose slightly but insignificantly. Inhibins are sensitive biochemical markers of ovarian activity in pill-free intervals.

PIP: Serum values of dimeric inhibin A and B were measured to assess the restoration of pituitary and ovarian activity during the pill-free interval in women taking combined oral contraceptives. 175 healthy women 18-35 years of age from five areas in Belgium were enrolled and monitored during routine gynecologic examinations. During the 7 day pill-free interval, inhibin B levels rose significantly in parallel with rising levels of follicle-stimulating hormone, luteinizing hormone, and estradiol. Progesterone levels were completely suppressed. Inhibin A levels rose slightly but insignificantly, reflecting an absence of development of preovulatory follicles. These findings indicate that inhibins are sensitive biochemical markers of ovarian activity in pill-free intervals. Inhibin B appears to be predominantly a product of the cohort of developing primary and subsequent early antral follicles, while inhibin A secretion is more indicative of dominant follicular and corpus luteum function.

Effectiveness of a pair-gain feeding strategy for individually fed, group-housed finishing pigs.

Crossbred barrows (n = 48) and gilts (n = 12) were used to examine the effectiveness of a pair-gain feeding strategy for individually fed, group-housed barrows. In a pair-gain feeding strategy, barrows were individually restricted to a feeding level at which their growth was similar to the mean growth of gilts with ad libitum access to feed. The purposes of this feeding strategy were to have barrows and gilts reach slaughter weight at the same time and to improve carcass traits of the barrows. At 29.8 +/- .4 kg BW, barrows were assigned to either the pair-gain or the ad libitum treatment. All pigs had free access to feed until they reached 60 kg BW. The experimental period was from 60 to 110 kg BW. The 12 group-fed gilts and 24 individually fed barrows (12 per pen) were also given free access to feed throughout the experimental period. The remaining 24 barrows (12 per pen) were put on a pair-gain feeding strategy. In the pair-gain feeding strategy, the weekly feed allowance of each barrow was based on its measured BW and computed energy conversion ratio and on the mean growth of the gilts. The barrows in the pair-gain treatment grew at the same rate as gilts. The ad libitum intake barrows grew faster (P < .05) and had a poorer energy conversion ratio for production than the barrows in the pair-gain treatment. The total energy conversion ratio, backfat thickness, and lean meat percentage were similar (P > .10) for the two treatments. In conclusion, the pair-gain feeding strategy was effective in achieving similar growth between barrows and gilts. The total energy conversion ratio and carcass traits of the barrows, however, were not improved.

Holoprosencephaly and postaxial polydactyly with normal chromosomes. Another observation of a new malformation syndrome; a case report.

A newborn boy is described with semilobar holoprosencephaly, cebocephaly with single nostril, median pseudocleft of upper lip, postaxial polydactyly, hypogenitalism, Hischsprung's disease and survival till the age of 13 weeks. Chromosomal analysis on lymphocytes was normal. Up to now, three other patients with this malformation complex have been described. Together with the present patient, they are apparently the first examples of a new malformation syndrome.

Using polar coordinates to measure variability in samples of Phenacolemur: a method of approach.

Polar coordinates can be used to quantify shapes on which homologous points cannot be readily identified such as lophs, edges, circumferences, outlines of areas, etc., This allows one to describe quantitatively characters, often diagnostic, that at present are not usually quantified and hence do not figure in the statistical analysis of variability that ought to accompany morphological descriptions in taxonomic work. Computer-driven plotters, using this data, provide an efficient means of graphing it, with great accuracy, in a variety of ways that can be used as an aid in qualitatively assessing variability in a sample or as a basis for further quantitative work. Principal component analysis of the data is essential to reduce the great quantity of measurements to a more manageable amount. It is also a valuable aid in interpreting the information. In the example using the Phenacolemur sample, it was shown with the data obtained from the use of polar coordinates in measuring that: (1) Discriminant functions can be used to distinguish between teeth that are very similar in shape and size, such as the Phenacolemur M1 and M2 and with which it is difficult to make such a distinction visually in an objective fashion. (2) It can be shown quantitatively that size is the only valid distinguishing criterion in splitting the AMNH Phenacolemur sample into three species and that the variability in shape is not significant.