Local climate and vernalization sensitivity predict the latitudinal patterns of flowering onset in the crop wild relative Linum bienne Mill.

BACKGROUND AND AIMS: The timing of flowering onset is often correlated with latitude, indicative of climatic gradients. Flowering onset in temperate species commonly requires exposure to cold temperatures, known as vernalization. Hence, population differentiation of flowering onset with latitude might reflect adaptation to the local climatic conditions experienced by populations. METHODS: Within its western range, seeds from Linum bienne populations (the wild relative of cultivated Linum usitatissimum) were used to describe the latitudinal differentiation of flowering onset to determine its association with the local climate of the population. A vernalization experiment including different crop cultivars was used to determine how vernalization accelerates flowering onset, in addition to the vernalization sensitivity response among populations and cultivars. Additionally, genetic differentiation of L. bienne populations along the latitudinal range was scrutinized using microsatellite markers. KEY RESULTS: Flowering onset varied with latitude of origin, with southern populations flowering earlier than their northern counterparts. Vernalization reduced the number of days to flowering onset, but vernalization sensitivity was greater in northern populations compared with southern ones. Conversely, vernalization delayed flowering onset in the crop, exhibiting less variation in sensitivity. In L. bienne, both flowering onset and vernalization sensitivity were better predicted by the local climate of the population than by latitude itself. Microsatellite data unveiled genetic differentiation of populations, forming two groups geographically partitioned along latitude. CONCLUSIONS: The consistent finding of latitudinal variation across experiments suggests that both flowering onset and vernalization sensitivity in L. bienne populations are under genetic regulation and might depend on climatic cues at the place of origin. The association with climatic gradients along latitude suggests that the climate experienced locally drives population differentiation of the flowering onset and vernalization sensitivity patterns. The genetic population structure suggests that past population history could have influenced the flowering initiation patterns detected, which deserves further work.

Comparative Study of Eclipse and RayStation Multi-Criteria Optimization-Based Prostate Radiotherapy Treatment Planning Quality.

Multi-criteria optimization (MCO) function has been available on commercial radiotherapy (RT) treatment planning systems to improve plan quality; however, no study has compared Eclipse and RayStation MCO functions for prostate RT planning. The purpose of this study was to compare prostate RT MCO plan qualities in terms of discrepancies between Pareto optimal and final deliverable plans, and dosimetric impact of final deliverable plans. In total, 25 computed tomography datasets of prostate cancer patients were used for Eclipse (version 16.1) and RayStation (version 12A) MCO-based plannings with doses received by 98% of planning target volume having 76 Gy prescription (PTV76D98%) and 50% of rectum (rectum D50%) selected as trade-off criteria. Pareto optimal and final deliverable plan discrepancies were determined based on PTV76D98% and rectum D50% percentage differences. Their final deliverable plans were compared in terms of doses received by PTV76 and other structures including rectum, and PTV76 homogeneity index (HI) and conformity index (CI), using a t-test. Both systems showed discrepancies between Pareto optimal and final deliverable plans (Eclipse: -0.89% (PTV76D98%) and -2.49% (Rectum D50%); RayStation: 3.56% (PTV76D98%) and -1.96% (Rectum D50%)). Statistically significantly different average values of PTV76D98%,HI and CI, and mean dose received by rectum (Eclipse: 76.07 Gy, 0.06, 1.05 and 39.36 Gy; RayStation: 70.43 Gy, 0.11, 0.87 and 51.65 Gy) are noted, respectively (p < 0.001). Eclipse MCO-based prostate RT plan quality appears better than that of RayStation.

Comparative Study of Plan Robustness for Breast Radiotherapy: Volumetric Modulated Arc Therapy Plans with Robust Optimization versus Manual Flash Approach.

A previous study investigated robustness of manual flash (MF) and robust optimized (RO) volumetric modulated arc therapy plans for breast radiotherapy based on five patients in 2020 and indicated that the RO was more robust than the MF, although the MF is still current standard practice. The purpose of this study was to compare their plan robustness in terms of dose variation to clinical target volume (CTV) and organs at risk (OARs) based on a larger sample size. This was a retrospective study involving 34 female patients. Their plan robustness was evaluated based on measured volume/dose difference between nominal and worst scenarios (ΔV/ΔD) for each CTV and OARs parameter, with a smaller difference representing greater robustness. Paired sample t-test was used to compare their robustness values. All parameters (except CTV ΔD98%) of the RO approach had smaller ΔV/ΔD values than those of the MF. Also, the RO approach had statistically significantly smaller ΔV/ΔD values (p < 0.001-0.012) for all CTV parameters except the CTV ΔV95% and ΔD98% and heart ΔDmean. This study's results confirm that the RO approach was more robust than the MF in general. Although both techniques were able to generate clinically acceptable plans for breast radiotherapy, the RO could potentially improve workflow efficiency due to its simpler planning process.

The role of growth hormone in the pathogenesis of postmenopausal osteoporosis.

The secretory response of somatotropic hormone (STH) to arginine hydrochloride stimulation (0.5 g/kg) was studied in 13 postmenopausal women. Eight showed evidence of osteoporosis, based on clinical and morphoradiological data and on metacarpal cortical thickness measurement, and five had normal bone mass. In addition, the response to levodopa (500 mg) was determined in four of the osteoporotic patients. Baseline STH concentrations in the osteoporotic subjects did not differ from those in the nonosteoporotic group, but the latter showed a significant increase over the former at 45, 60, 90, and 120 minutes after stimulation. Similar findings were obtained with levodopa stimulation. Without necessarily implying a cause-effect relationship, our data appear to support the hypothesis that the poor secretory response of STH may be to some degree responsible for the osteopenia observed during the climateric.

Crush fracture syndrome in senile osteoporosis: a nutritional consequence?

Osteoporosis is a very important age-related health problem. The body's composition changes with age, and these changes are a true reflection of aging and of the individuals's nutritional status. Mineral content changes have been reported in vertebral osteoporosis. Interestingly, enough, there have not been reports on concomitant water, fat, and fat-free mass changes associated with this condition. In this report, changes in the latter parameters are compared between patients with osteoporosis and controls. The four components (water, mineral, fat, and fat-free mass) were found significantly reduced (p less than 0.001) in osteoporosis. Serum albumin and protein mass were also reduced (p less than 0.001).

Effects of zinc supplementation on vertebral and femoral bone mass in rats on strenuous treadmill training exercise.

The hypothesis that a zinc (Zn) deficit may cause osteopenia in athletes is well founded. In rats exposed to strenuous exercise, we evaluated the effect of a zinc supplement on femoral and vertebral bone mass determined by dual-energy X-ray absorptiometry. Four lots of 93-day-old female Wistar rats were studied. A control group of 30 rats were not manipulated (Zn- Ex- group). The experimental group of 40 rats was fed a diet supplemented with an additional 20% of Zn/kg of feed; this group was divided into two groups of 20 rats each, one that did not exercise (Zn+ Ex-) and one that did (Zn+ Ex+). A group of 15 rats exercised but did not receive a zinc supplement (Zn- Ex+ group). Training consisted of treadmill running for 5 out of 7 days over an 11-week period. Initial speed, running time, and treadmill speed were increased gradually. Analysis of variance with the Bonferroni/Dunn test showed that the length, weight, bone mineral content (BMC), and bone mineral density (BMD) of the femur were less in the Zn- Ex+ group than in the others (p < 0.008), and the weight, BMC, and BMD of the fifth lumbar vertebra also were lower in the Zn- Ex+ group than in the others (p < 0.008). These findings confirm the adverse effects of strenuous exercise (treadmill running) on bone tissue in rats and the effectiveness of zinc supplementation in preventing it.

Biochemical assessment of acute and chronic treatment of Paget's bone disease with calcitonin and calcium with and without biphosphonate.

Response to acute and chronic administration of calcitonin and calcium and of biphosphonates (EHDP) was evaluated in 14 patients with Paget's bone disease who were grouped on the basis of homogeneous disease activity, as appraised by bone involvement and alkaline phosphatase and hydroxyproline levels. At first, 100 MRC U of calcitonin followed 4 hours later by 500 mg of elemental calcium were given for 10 days; a significant (p less than 0.001; paired and unpaired Student t test) reduction in alkaline phosphatase (-25%) and hydroproline (-55%) was observed. Subsequently, 5 mg/kg/day of EHDP was given for 20 days. Both parameters increased to levels similar to basal values. These increases were significant (p less than 0.001 for the paired and unpaired Student test) compared with those obtained after calcitonin administration; alkaline phosphatase rose +27% and hydroxproline +135%. After this, patients were divided into 2 groups (A and B). Group A was treated with calcitonin and calcium, at the dosage indicated above, for 10 days a month during 6 months. Group B continued with the same protocol with the addition of EHDP for the 20 days during which calcitonin and calcium were not given. The results of 6 months of treatment showed that calcitonin was more active and suggested that EHDP diminishes hormonal effects. These results also demonstrate a short-term absence of EHDP activity.

Heterogeneity of trabecular and cortical postmenopausal bone loss: a longitudinal study with pQCT.

Eighty-one women were studied longitudinally to measure trabecular bone mineral density (BMDTrab) and cortical bone mineral density (BMDCorti) in the distal radius by peripheral quantitative computed tomography (pQCT) at intervals of about 1 year and to calculate the rate of percent change/year. Fifty-three women were naturally postmenopausal [mean age 63.3 +/- 5.3 years, age at menopause 50.7 +/- 3.8 years, 13 years since menopause (YSM)] and 28 had been ovariectomized (mean age 52.7 +/- 5.8 years, age at menopause 39.5 +/- 5.0 years, 13 YSM). There was no difference between groups (ANOVA) in the rate of percent change/years in BMDTrab (p = 0.692), but there was in BMDCorti (p = 0.020). When the women who had either gained or lost bone mass were compared (chi-square test), only BMDCorti differed significantly (p = 0.018). Considering > -2.5% change/years as the limit for rapid bone mass loss, BMDTrab values showed that 43% of the naturally postmenopausal women and 42.7% of the ovariectomized women had rapid bone loss (p ns). On the basis of BMDCorti values, 45% of the naturally postmenopausal women and 28.4% of the ovariectomized women had rapid bone loss (p = 0.018). Height, weight, body mass index (BMI), age, YSM, and years of reproductive life did not differ (ANOVA) between the women who gained or lost either BMDTrab or BMDCorti. Using Fisher's r to z and partial correlation adjusted for age and YSM of the percent change/year in BMDTrab and BMDCorti in the overall group and in each menopausal group, only BMDCorti differed.

Metacarpal cortical thickness by computed radiography in osteoporosis.

Computed radiography was used to make radiogrammetric measurements of the second metacarpal in 240 women, 180 considered normal and 60 osteoporotic. These measurements had a coefficient of variation for the external diameter of 0.74% in normal women and 0.75% in osteoporotic women, and for the internal diameter of 2.4% and 2.03%, respectively. The group of women with osteoporosis was divided according to external diameter and internal diameter into a group with osteoporosis due to increased bone resorption (61.1%, normal external diameter and increased internal diameter), and osteoporosis due to deficient bone formation (26.1%, decreased external diameter and normal internal diameter). In the remaining subjects (12.8%), osteoporosis was attributed to both mechanisms. There was a significant linear regression between internal diameter and tartrate-resistant acid phosphatase concentration (p < 0.0001) in the group of increased bone resorption, which was absent (p = ns) in the group with deficient bone mass formation. No changes were observed in the size of the two groups. The low coefficient of variation of radiogrammetric measurements with computed radiography validate it as an accurate technique for bone mass studies. Moreover, it has the additional advantage of permitting determination of the proportion of women with osteoporosis due to increased bone resorption and/or deficient bone mass formation.

Bone mineral content and body composition in postpubertal cyclist boys.

The effect of sports activity on bone mass was assessed by dual-energy X-ray absorptiometry in a group of 22 young cyclists aged 16.2 +/- 0.7 years. These athletes trained for 10 hours a week for over two years. Bone mass values were compared with those of 27 sedentary youngsters aged 16.9 +/- 0.3 years. There were no differences in total body bone mineral (TBBM) between groups. The leg bone mineral content (LBMC), body weight, and percentage fat were lower in the cyclists than in controls (p < 0.02, p < 0.01, and p < 0.001 respectively). No changes were observed when TBBM was normalized for weight. The changes observed earlier in LBMC disappeared when normalized for body weight. These results suggest that cycling does not stimulate bone mass in youngsters, and that the type, quality, and length of sports activity need to be defined.

Oncogenous osteomalacia: a new case secondary to a malignant tumor.

A case of oncogenous osteomalacia secondary to a fibrous malignant histiocytoma in a 31-year-old male is described. The patient also demonstrated a lupuslike anticoagulant. Clinical signs of osteomalacia preceded by 9 years those of the tumor, a feature occurring in only 8% of these malignancies. Surgical resection of the tumor and surrounding tissues was followed by a clinical improvement and a return to normal of serum phosphorus and tubular reabsorption of phosphate, though the lupuslike anticoagulant persisted. This first description of a fibrous malignant histiocytoma with associated osteomalacia and lupuslike anticoagulant makes compulsory the inclusion of these syndromes among those already described that may appear with this tumor.

Electrophoretic mobility of external invertase from free and gel-immobilized yeast cells.

Electrophoretic mobility of secreted invertase (E.C. 3.2.1.26) from gelatin-immobilized yeast cells was analysed and compared with that of secreted invertase from freely suspended batch-grown cells. Invertase from immobilized cells showed a lower mobility after 24 h of incubation, in medium containing either glucose or raffinose as carbon source. Changes in invertase mobility were also followed in a time course both for immobilized and for freely suspended batch-grown cells. Mobility of invertase from free cells increased after approximately 15 h of incubation, independently of the carbon source, whilst that of invertase from immobilized cells remained constant. The differences observed were attributed to a different level of glycosylation of the protein moiety in free and immobilized cells. The amount of mannoproteins in the cell walls of immobilized cells was also investigated by ConA-ferritin labelling and quantification of ferritin particle density in ultrathin sections; the results of this experiment showed a higher content of mannoproteins in the walls of immobilized cells when compared with free cells. As a whole, these results are indicative of physiological changes that can be ascribed to the peculiar microenvironment of gel-immobilized cells.

Initial steps of wall protoplast regeneration in Candida albicans.

Cell wall regeneration of individual Candida albicans yeast and mycelial protoplasts was studied with confocal and electron microscopy using polyclonal antibodies and lectins. Quantitative measurements of the fluorescence emitted by individual protoplasts during the process of regeneration indicate that chitin is the first polymer to be laid down, whereas beta (1,3)- and beta (1,6)glucan are incorporated at a later stage. Mannoproteins were found on the surface of fresh protoplasts and those newly synthesized were then deposited with time. During the first steps of wall regeneration, the proteins that interacted covalently with chitin or glucan were different, but the same species were found linked to each polymer in yeast and mycelial regenerating forms. The aggregates formed by regenerating protoplasts were shown to be due to the chitin and mannoprotein network initially laid.

Behavior of bone mass measurements. Dual energy x-ray absorptiometry total body bone mineral content, ultrasound bone velocity, and computed metacarpal radiogrammetry, with age, gonadal status, and weight in healthy women.

RATIONALE AND OBJECTIVES: Bone mass as measured by dual energy x-ray absorptiometry varies with body weight. The authors studied the behavior of bone mass measurements made by ultrasound bone velocity and metacarpal radiogrammetry in relation to body weight. METHODS: Eighty healthy women were studied: 40 post-menopausal and 40 premenopausal (mean age 60 +/- 6 and 38 +/- 8 years, respectively). The authors performed in every subject the following studies: a radiograph of the nondominant hand for metacarpal cortical thickness, a study of the 2nd to 5th proximal phalanges for ultrasound bone velocity, and total bone mineral content by dual energy x-ray absorptiometry. RESULTS: The measurements obtained with the three methods correlated significantly with each other (P < 0.0001). The only parameter related significantly with weight were total bone mineral content (P < 0.0001). In the premenopausal women, age did not correlate with any measurement. In the postmenopausal women, age correlated significantly with the three measured parameters (P < 0.0058 to P < 0.0001). CONCLUSIONS: Weight did not influence ultrasound bone velocity and metacarpal cortical thickness measurements.

Ultrasound bone velocity on proximal phalanges in premenopausal, perimenopausal, and postmenopausal healthy women.

RATIONALE AND OBJECTIVES: The authors studied premenopausal, perimenopausal, and postmenopausal women to determine if ultrasound bone velocity (UBV) on proximal phalanges of women reflect bone changes related to gonadal status and age. METHODS: A total of 166 healthy women-64 postmenopausal women (mean age 58.7 +/- 9.4 years), 41 perimenopausal women (mean age 49.5 +/- 2.9 years), and 61 premenopausal women (mean age 36.8 +/- 7.1 years)-were studied. All the women underwent UBV study of the 2nd to 5th proximal phalanges on the nondominant hand and the mean value of all ultrasound measurements was calculated. RESULTS: The postmenopausal women had a UBV that differed significantly, one-way analysis of variance, from that of the perimenopausal women and premenopausal women (both P < 0.001). The UBV measurements of the perimenopausal women differed significantly from those of the premenopausal women (P < 0.01). Simple linear regression analysis of the relation between UBV and age showed that this was significant and negative in the overall group of women (r = -0.69; P < 0.0001), significant in the perimenopausal (r = -0.66; P < 0.001) and postmenopausal women (r = -0.69; P < 0.001) and nonsignificant in the premenopausal women (r = 0.08; P not significant). In the postmenopausal women, the correlation between UBV and years since menopause was larger (r = -0.71; P < 0.0001) than the correlation between UBV and chronological age. CONCLUSIONS: Ultrasound bone velocity of the phalanx, as a method for measuring changes in bone with age, has a precision that makes it possible to detect changes in bone mass in perimenopausal women and may perform similarly to other bone mass measurements.

Impact of weight in obese subjects on bone speed of sound.

RATIONALE AND OBJECTIVES: The authors determined the effect of obesity on measurements of amplitude-dependent speed of bone ultrasound (Ad-SOS [m/sec]) and compared them to the total body bone mineral content (TBBMC/g). METHODS: A total of 25 women were studied (mean age 41.8 +/- 10.2 years). In all the subjects, body mass index (BMI) exceeded 30 kg/m2 (range, 31.12-47.47 kg/m2); mean body weight was 104 +/- 17 kg. Ad-SOS was measured at the proximal phalanges and TBBMC in whole body with dual-energy x-ray absorptiometry. RESULTS: Correlation study (Fisher's r to z) showed that Ad-SOS correlated negatively with weight (r = -0.85, P < 0.0001) and with TBBMC (r = -0.71, P < 0.0001). The correlation between TBBMC and weight was r = 0.76, P < 0.0001. Body fat percentage correlated partially with TBBMC (r = 0.40, P < 0.05) and negatively with Ad-SOS (r = -0.75, P < 0.0001). When the correlation test was adjusted for weight (partial correlation), the correlation between Ad-SOS and TBBMC was not significant (r = -0.21, P = NS), and the correlation between Ad-SOS and weight continued to be inversely significant (r = -0.67, P < 0.0001). CONCLUSIONS: The results showed a clearly negative effect of weight on Ad-SOS measurements and indicated the limitations of this technique when employed in overweight and obese patients. Broad-band ultrasound attenuation and speed of sound, two commonly measured variables in bone ultrasound studies, may be differently affected by soft tissue.

Do ultrasound measurements reflect bone microarchitecture rather than bone mass?: An in vitro study of the rat femur with the use of ultrasound, densitometry, and histomorphometry.

RATIONALE AND OBJECTIVES: In an experimental study in 40 rat femurs, the authors correlated the amplitude-dependent speed of bone ultrasound (Ad-SOS) with the bone mineral content and density and with the bone trabecular connectivity: trabecular bone volume, trabecular number, trabecular thickness, and trabecular separation to evaluate and compare the usefulness of the Ad-SOS to determine bone quantity and/or quality. METHODS: Bone mineral content and density were determined with dual-energy x-ray absorptiometry. Trabecular connectivity was determined with histomorphometric techniques. RESULTS: There was a strong correlation between the Ad-SOS and the other parameters studied, with a particularly high positive correlation with trabecular bone volume and trabecular thickness, and an inverse correlation with trabecular separation. The correlation was weaker with the bone mineral content and bone mineral density and with the trabecular number. For the trabecular separation, the correlation was significant in all cases, but it was negative. CONCLUSIONS: Bone ultrasound, in this case Ad-SOS, defines the quality of the bone in terms of trabecular architecture rather than bone density; however, this conclusion is valid only for the rat femur model that the authors used.

The effect of supplemental copper on osteopenia induced by ovariectomy in rats.

OBJECTIVE: The effect of a copper supplement on preventing bone mass loss induced by ovariectomy in rats was investigated. DESIGN: Three groups of fifteen 100-day-old female Wistar rats, each with a mean initial weight of approximately 260 g per animal, were selected for a 30-day experiment. One group of 15 ovariectomized rats was fed a diet supplemented with 15 mg of copper per kilogram of feed. The other two groups: 15 ovariectomized and 15 Sham- ovariectomized rats did not receive the supplement. Morphometric (weight and length) and densitometric studies with dual-energy x-ray absorptiometry were performed on the whole femur and the fifth lumbar vertebra of each animal at the end of the 30-day period. RESULTS: The ovariectomized rat group fed a diet supplemented with copper did not show the bone mass loss at the axial (fifth lumbar vertebra) or peripheral (femur) level that was evidenced in the ovariectomized group. CONCLUSIONS: The results of the measurement of axial and peripheral bones show that a supplement of copper may have a potential therapeutic application in the treatment and prevention of involutional osteoporosis.

Correlation of ultrasound bone velocity with dual-energy X-ray bone absorptiometry in rat bone specimens.

RATIONALE AND OBJECTIVES: To investigate bone mass measurements by ultrasound bond velocity (UBV) in bone specimens obtained from experimental animals. METHODS: The authors made UBV measurements in 40 femurs and tibias dissected from Sprague-Dawley rats (14 weeks-old, mean weight 290 g) and compared them with bone densitometric measurements made on the same material using dual-energy x-ray absorptiometry (DXA). RESULTS: The coefficient of variation for UBV measurements, based on values obtained in five femurs and five tibias at different times, was 0.2% and 0.3% respectively. Regression studies yielded a correlation between UBV and bone mineral density in femur of r = 0.87 (P < 0.0001) and with bone mineral content of r = 0.65 (P < 0.0001); in the tibia similar levels of significance were obtained. The correlation between femur weight and UBV was r = 0.51 (P < 0.0005) and with bone mineral content it was r = 0.79 (P < 0.0001). Partial correlation between UBV and femur bone mineral density, with respect to bone weight, was r = 0.68 (P < 0.001), and with femur bone mineral content was r = 0.71 (P < 0.0001). In the tibia measurements were similarly significant. CONCLUSIONS: Measurements of bone mass made with ultrasound transmission velocity are precise correlate well with DXA measurements.

Influence of soft tissue (fat and fat-free mass) on ultrasound bone velocity: an in vivo study.

RATIONALE AND OBJECTIVES: The authors determine the relative effect of soft-tissue compartments, body fat (percent [%Bfat] and weight [Bfat kg]) and fat-free mass (FFM kg), on measurements of ultrasound bone velocity (UBV m/second). METHODS: The authors measured UBV in proximal phalanxes and body fat and fat-free mass by near infrared interactance in 40 healthy premenopausal women (mean age +/- standard deviation 28.2 +/- 3.8 years). RESULTS: Correlation study (Fisher's r to z) showed that UBV correlated negatively with %Bfat (r = -0.61, P < 0.0001), Bfat kg (r = -0.56, P = 0.0001) and marginally with body weight (r = -0.33, P = 0.0403), but did not correlate with FFM kg or H2O L (both r = -0.08, P not significant). When the correlation test was adjusted for weight and age (partial correlation), the negative correlation between UBV and %Bfat persisted (r = -0.54, P < 0.0005; and r = -0.63, P < 0.0001, respectively) and the correlation with FFM kg, adjusted for weight, became positive and significant (r = 0.55, P < 0.0005). CONCLUSIONS: These results, to our knowledge, are the first to be obtained by in vivo evaluation of UBV in relation to body fat and fat-free mass. Body fat, but not fat-free mass, was the main factor affecting UBV. This confirms the deficiency of UBV measurements, considering that obesity is a protective factor for bone mass.