Anatomical Regions (anatomical + regions)

Distribution by Scientific Domains
Distribution within Medical Sciences

Selected Abstracts

Schizophrenia; from structure to function with special focus on the mediodorsal thalamic prefrontal loop

B. Pakkenberg
Objective:, To describe structural and biochemical evidence from postmortem brains that implicates the reciprocal connections between the mediodorsal thalamic nucleus and the prefrontal cortex in cognitive symptoms of schizophrenia. Method:, The estimation of the regional volumes and cell numbers was obtained using stereological methods. The biochemical analyses of molecular expression in postmortem brain involve quantitative measurement of transcripts and proteins by in-situ (RNA) or Western blot/autoradiography in brains from patients with schizophrenia and comparison subjects. Results:, Stereological studies in postmortem brain from patients with schizophrenia have reported divergent and often opposing findings in the total number of neurons and volume of the mediodorsal (MD) thalamic nucleus, and to a lesser degree in its reciprocally associated areas of the prefrontal cortex. Similarly, quantitative molecular postmortem studies have found large inter-subject and between-study variance at both the transcript and protein levels for receptors and their interacting molecules of several neurotransmitter systems in these interconnected anatomical regions. Combined, large variation in stereological and molecular studies indicates a complex and heterogeneous involvement of the MD thalamic-prefrontal loop in schizophrenia. Conclusion:, Based on a considerable heterogeneity in patients suffering from schizophrenia, large variation in postmortem studies, including stereological and molecular postmortem studies of the MD thalamus and frontal cortex, might be expected and may in fact partly help to explain the variable endophenotypic traits associated with this severe psychiatric illness. [source]

Cytology of the central zone of the prostate

Lars Egevad M.D., Ph.D.
Abstract The prostate has three anatomical regions: the peripheral, transition, and central zones (CZ). The CZ has distinct histological features, but its cytological morphology has not been described. This study was done on surgical specimens to ensure that samples were representative of the CZ, and that no prostatic intraepithelial neoplasia (PIN) or cancer contaminated the smears. An incision was made in the CZ of 51 prostatectomy specimens, and cells were scraped from cut surfaces. After exclusion of samples contaminated by PIN or cancer or with poor cell yield, 39 Giemsa-stained smears remained for analysis. Large branching epithelial sheets with geographic architecture and crowded nuclei were seen in 97% of smears. Epithelial clusters with elongated palisaded nuclei were identified in 80% of cases, but were always a minor component. Visible nucleoli (97%), cytoplasmic vacuoles (97%), and smooth muscle cells in the background (95%) were common. Blue-green cytoplasmic granules resembling seminal vesicle pigment were seen in 97%. Magenta-colored cytoplasmic pigment, similar to granules seen in other regions of the prostate, was found in 74%. Recognition of CZ epithelium as a benign constituent of prostate cytology is important because elongated cells, crowded nuclei, and visible nucleoli may otherwise be misinterpreted as PIN or cancer. Diagn. Cytopathol. 2003;28:239,244. 2003 Wiley-Liss, Inc. [source]

Surgical treatment options for hidradenitis suppurativa and critical review of own experience

Wolfgang Christian Marsch
HS (acne inversa) is a chronic, progressive, initially inflammatory, ultimately a fistulating and scarring disease affecting apocrine gland-bearing skin areas. Late phases afford a broad surgical removal of affected skin areas including subcutaneous fatty tissue, with secondary mesh grafting after a period of granulation tissue formation. Fifty-three patients have been treated surgically at our Dermatology Department. Long-term results are excellent concerning satisfaction of the patients and functional objectives. Local recurrences or development of new lesions in formerly unaffected areas were noticed only in some patients who did not stop smoking. Patient details were as follows: gender distribution: male (M) 20 (38%), female (F) 33 (62%), age: M 19,62 (average 40.7), F 15,56 (average 35.4), onset: M 16,57 (32.2), F 8,50 (25.5), duration: 3 months to 37 years (8.0), F 6 months to 37 years (9.9). Sites mainly affected: axillary and perigenital. Specific regions for men: perineum and rima ani, for women: inguinal, submammary and abdominal. Multiple anatomical regions involved: men 40%, women 91%. Familiarity 0.4%. Associated acne papulo-pustulosa or nodulo-cystica (=conglobata): 19%. Cigarette smokers: men 100%, women 67%. Excised material from each operation was carefully examined histologically. The results endorse the concept of ,acne inversa' by recognizing a perifollicular accumulation of lymphocytes simultaneously at different infrainfundibula of terminal hair follicles. However, a follicular hyperkeratosis seems secondary to this, follicular perforation, and a combination of sinus, abscess and scar formation are most obviously tertiary events. Therefore, HS seems to be an inflammatory, probably an immunological disease with an initially strictly dermal target, even followed by an intradermal horizontal propagation. Laser flux imaging could visualize the subclinical peripheral extension of the basically dermal perifollicular inflammation. Biologics may have a beneficial effect on these early or perpetuating inflammatory events; however, thus far surgery remains the first-line therapy in late phases of the disease. [source]

Proton pump inhibitor omeprazole use is associated with low bone mineral density in maintenance haemodialysis patients

A. Kirkpantur
Summary Objective:, Limited studies have shown that proton pump inhibitor (PPI) therapy may decrease bone density or insoluble calcium reabsorption through induction of hypochlorhydria. However, PPI therapy may also reduce bone resorption via inhibition of osteoclastic vacuolar proton pumps. The aim of this study was to determine whether the opposing effects of PPI therapy may cause clinically important alterations in bone mineral densitometry (BMD) parameters in maintenance haemodialysis patients. Methods:, Sixty-eight maintenance haemodialysis patients were enrolled in this study. Patients were classified into two groups involving users of PPI therapy (omeprazole 20 mg/day, group 1, n = 36 patients) and non-users of acid suppression drugs (group 2, n = 32 patients). Patients had radius, hip and spine BMD assessed by dual-energy X-ray absorptiometry. Results:, The mean duration of PPI therapy with omeprazole was 27 5 months. The users of PPI therapy had lower values of bone mineral density and T -scores at the anatomical regions than non-users of acid suppression drugs. Serum calcium and phosphate levels, calcium-phosphate product and serum intact parathormone levels and the ratio of users of vitamin D therapy were similar among groups. A mutivariable adjusted odds ratio for lower bone density associated with more than 18 months of omeprazole, when all the potential confounders were considered, was 1.31 in the proximal radius, 0.982 in the femur neck, 0.939 in the trochanter and 1.192 in the lumbal spine. Conclusion:, The present data suggest that PPI therapy should be cautiously prescribed in maintenance haemodialysis patients, especially with lower BMD values. [source]

Heritability of bone density: Regional and gender differences in monozygotic twins

Kevin Y. Tse
Abstract Bone mineral density (BMD) is a measure of a person's skeletal mineral content, and assessing BMD by dual x-ray absorptiometry (DEXA) can help to diagnose diseases of low bone density. In this study, we determine the heritability of BMD in male and female monozygotic twin subjects using DEXA in 13 specific anatomical regions. In an attempt to quantify the genetic contribution of gender and skeletal region to BMD heritability, we scanned 14 pairs of identical twins using DEXA and calculated the broad-sense heritability coefficient (H2) in each of the 13 different body regions. The region of the body that was most heritable for both genders was the head (H2,,,95%). When males were compared to females, H2 values for male hip (H2,=,87%) and lower extremities (H2,=,90%) were higher than those in females (H2,=,49% and 56%, respectively). Conversely, H2 value for the female pelvis (H2,=,68%) was higher than that for males (H2,=,26%). These data show that different regions of the skeleton exhibit different degrees of heritability, and that the variation depends on gender. 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:150,154, 2009 [source]

A detailed assessment of the pattern of moxidectin tissue distribution after pour-on treatment in calves

J. M. Sallovitz
The use of topical (pour-on) administration of endectocide drugs in cattle has reached world-wide acceptance. However, only limited information is available on the kinetic behaviour for topically administered moxidectin (MXD). To improve our understanding of the relationship between pharmacokinetics and efficacy for pour-on preparations, MXD concentration profiles were measured in tissues of endo- and ectoparasites location over 35 days postadministration. MXD distribution to the fluid content and mucosal tissue of the abomasum and different intestinal sections (duodenum, ileum, caecum and colon) was assessed. The comparative patterns of MXD distribution to skin and hypodermic tissue from different anatomical sites (backline, rib cage, thigh and face) were also investigated following the pour-on administration. Wide tissue distribution and long residence time characterized the kinetics of topically administered MXD. MXD was recovered between 1 and 35 days post-treatment in all the tissues investigated. The highest MXD availabilities were observed in the skin layers at the site of administration (backline) and in the fat tissue. The fluid contents of different intestinal sections showed MXD concentrations higher than those measured in their respective mucosal tissues, particularly at day 1 post-treatment. MXD concentrations in the skin (epidermis + dermis) were higher than those measured in the hypodermic tissue. Large differences in the availability of MXD in skin from different anatomical regions (backline > rib cage > thigh > face) were observed. The low plasma and the high skin availability indicate the formation of a skin depot of the drug, being released slowly to the plasma and reaching concentrations in systemic tissues (abomasal mucosa, lungs, etc.) similar to those measured after subcutaneous administration. These findings demonstrate that target parasites may be exposed to markedly different drug concentrations according to their location sites, which is particularly relevant for ectoparasites located in different anatomical regions. Knowledge of the tissue distribution of topically administered endectocides contributes to understand the differences observed in efficacy and/or persistence of activity and to optimize their use in cattle. [source]

Long-term fine caliber hair removal with an electro-optic Q-switched Nd:YAG Laser,

Abnoeal D. Bakus PhD
Abstract Background In spite of major advances in hair removal therapy, fine caliber hair remains a significant challenge for laser- and light-based devices. Objective Evaluate a novel Electro-Optic (EO) Q-switched Nd:YAG laser for pigmented fine caliber hair removal in the Standard Single and a double pulse (DP) mode. Methods Eleven patients underwent four laser treatments at monthly intervals. Bilateral anatomical regions received to one side the standard single pulse (SSP) while the other side the DP option. Blinded investigators conducted hair counts at 6 months post-treatment and after 24 months. Patients assessed hair loss and discomfort. Six patients rated their satisfaction at 6 months. Results At 6 months, investigators found a reduction of 50% in hair counts with the DP and 46% with standard pulse. Ninety percent in DP and 50% in SSP reported none to mild discomfort. Transient erythema and edema was observed with a lower severity rating with the DP. There were no other untoward effects. 83.3% of patients who completed the study at 6 months expressed satisfaction with the results. At 24 months hair loss was maintained at the same rate. Conclusion The EO Q-switched Nd:YAG laser is an effective option for the permanent treatment of unwanted fine hair and has a high-patient satisfaction rate. There is less therapeutic discomfort in the DP mode. Lasers Surg. Med. 42:706,711, 2010 2010 Wiley-Liss, Inc. [source]

Two-point water-fat imaging with partially-opposed-phase (POP) acquisition: An asymmetric Dixon method,

Qing-San Xiang
Abstract A novel two-point water-fat imaging method is introduced. In addition to the in-phase acquisition, water and fat magnetization vectors are sampled at partially-opposed-phase (POP) rather than exactly antiparallel as in the original Dixon method. This asymmetric sampling encodes more valuable phase information for identifying water and fat. From the magnitudes of the two complex images, a big and a small chemical component are first robustly obtained pixel by pixel and then used to form two possible error phasor candidates. The true error phasor is extracted from the two error phasor candidates through a simple procedure of regional iterative phasor extraction (RIPE). Finally, least-squares solutions of water and fat are obtained after the extracted error phasor is smoothed and removed from the complex images. For noise behavior, the effective number of signal averages NSA* is typically in the range of 1.87,1.96, very close to the maximum possible value of 2. Compared to earlier approaches, the proposed method is more efficient in data acquisition and straightforward in processing, and the final results are more robust. At both 1.5T and 0.3T, well separated and identified in vivo water and fat images covering a broad range of anatomical regions have been obtained, supporting the clinical utility of the method. Magn Reson Med, 2006. 2006 Wiley-Liss, Inc. [source]

Zebra finch sexual differentiation: The aromatization hypothesis revisited

Juli Wade
Abstract Zebra finches have emerged as an outstanding model system for the investigation of the mechanisms regulating brain and behavior. Their song system has proven especially useful, as the function of discrete anatomical regions have been identified, and striking parallels exist between the morphology of these regions and the level of their function in males and females. That is, the structures are substantially more developed in males, who sing, compared to females, who do not. These parallels extend from higher (telencephalic) centers to the brainstem motor nucleus that innervates the muscles of the vocal organ. Other dimorphic aspects of reproduction in the zebra finch, such as copulatory behaviors and sexual partner preference, however, are not associated with known sex differences in anatomy. In many species, sex differences in neural and peripheral structures and behavior are regulated by secretions from the gonads, which of course are sexually dimorphic themselves. In birds, sex differences at all of these levels (gonad, brain, and behavior) can be mediated by steroid hormones. However, it is not entirely clear that gonadal secretions normally participate at all of the levels. This paper reviews the evidence relating to the role of gonadal steroids in the sexual differentiation of reproductive behaviors and the central and peripheral structures known to regulate them in zebra finches, with a focus on estradiol, which has been most extensively studied in the masculinization of song system morphology and function. Microsc. Res. Tech. 54:354,363, 2001. 2001 Wiley-Liss, Inc. [source]

Which cranial regions reflect molecular distances reliably in humans?

Evidence from three-dimensional morphology
Knowledge of the degree to which various subsets of morphological data reflect molecular relationships is crucial for studies attempting to estimate genetic relationships from patterns of morphological variation. This study assessed the phylogenetic utility of six different human cranial regions, plus the entire cranium. Three-dimensional landmark data were collected for 83 landmarks from samples of skulls from 14 modern human populations. The data were subsequently divided into anatomical regions: basicranium, upper face, mandible, temporal bone, upper jaw, cranial vault, and a subset of points from around the entire cranium. Depictions of population molecular distances were calculated using published data on microsatellites for the same or closely related populations. Distances based on morphological variation of each of the anatomical regions were compared with molecular distances, and the correlations assessed. The morphology of the basicranium, temporal bone, upper face, and entire cranium demonstrated the highest correlations with molecular distances. The morphology of the mandible, upper jaw, and cranial vault, as measured here, were not significantly correlated with molecular distances. As the three-dimensional morphology of the temporal bone, upper face, basicranium, and entire cranium appear to consistently reflect genetic relationships in humans, especially with more reliability than the cranial vault, it would be preferable to focus on these regions when attempting to determine the genetic relationships of human specimens with no molecular data. Am. J.Hum. Biol., 2009. 2008 Wiley-Liss, Inc. [source]

Evaluation of postmortem changes in tissue structure in the bottlenose dolphin (Tursiops truncatus)

Megan F. Mckenna
Abstract Postmortem changes in geometry, density, and sound speed within organs and tissues (melon, bone, blubber, and mandibular fat) of the dolphin head were evaluated using computed tomography (CT) scans of live and postmortem bottlenose dolphins (Tursiops truncatus). Specimens were classified into three different treatment groups: live, recently dead, and frozen followed by thawing. Organs and tissues in similar anatomical regions of the head were compared in CT scans of the specimens to identify postmortem changes in morphology. In addition, comparisons of Hounsfield units in the CT scans were used to evaluate postmortem changes in the density of melon, bone, blubber, and mandibular fat. Sound speed measurements from melon, blubber, connective tissue, and muscle were collected from fresh and frozen samples in the same specimen to evaluate effects due to freezing and thawing process on sound speed measurements. Similar results in tissue and organ geometry, density, and sound speed measurements suggested that postmortem material is a reliable approximation for live melon, bone, blubber, muscle, connective tissue, and mandibular fat. These results have implications for examining viscoelastic properties and the accuracy of simulating sound transmission in postmortem material. Anat Rec, 290:1023,1032, 2007. 2007 Wiley-Liss, Inc. [source]

Therapeutic efficacy of topical hydrocortisone aceponate in experimental flea-allergy dermatitis in dogs

S Bonneau
Objective To evaluate the treatment efficacy of a topical spray containing hydrocortisone aceponate (HCA) on dogs with flea-allergy dermatitis (FAD). Design A controlled clinical study was conducted on dogs with experimentally induced FAD. Sixteen laboratory beagles with mild to moderate clinical signs were divided into two groups. The test group received HCA by topical spray once daily for 7 days, while the control group did not. Pruritic events (time and frequency) were videotaped and then scored. Clinical signs (erythema, papules, excoriation and alopecia) present on four anatomical regions were monitored and their severity directly assessed. Results After 2 days, pruritus was reduced by 94% in the treatment group and by 24% in the control group (P = 0.014) in cumulative time, and by 86% versus 34% (P = 0.034) in frequency. The HCA spray also resulted in significant improvements in overall clinical signs: 23% versus 0% in the control group (P = 0.0006) on day 3 and 43% versus 15% in the control group (P = 0.0006) on day 7. During the 7-day trial, no drug-related adverse effects were observed. Conclusions Topical treatment with HCA showed a rapid and potent antipruritic effect on dogs with FAD. HCA also demonstrated significant overall therapeutic effects on FAD-associated skin lesions. [source]

Does the skull carry a phylogenetic signal?

Evolution, modularity in the guenons
Form and genes often tell different stories about the evolution of animals, with molecular data generally considered to be more objective than morphological data. However, form provides the basis for the description of organisms, and the study of fossils crucially depends on morphology. Complex organisms tend to evolve as ,mosaics', in which parts may be modified at varying rates and in response to different selective pressures. Thus, individual anatomical regions may contain different phylogenetic signals. In the present study, we used computerized methods to ,dissect' the skulls of a primate clade, the guenons, into functional and developmental modules (FDM). The potential of different modules as proxies for phylogenetic divergence in modern lineages was investigated. We found that the chondrocranium was the only FDM in which shape consistently had a strong and significant phylogenetic signal. This region might be less susceptible to epigenetic factors and thus more informative about phylogeny. The examination of the topology of trees from the chondrocranium suggested that the main differences evolved at the time of the radiation of terrestrial and arboreal guenons. However, phylogenetic reconstructions were found to be strongly affected by sampling error, with more localized anatomical regions (i.e. smaller/less complex FDMs) generally producing less reproducible tree topologies. This finding, if confirmed in other groups, implies that the utility of specific FDMs for phylogenetic inference could, in many cases, be hampered by the low reproducibility of results. The study also suggested that uncertainties due to sampling error may be larger than those from character sampling. This might have implications for phylogenetic analyses, which typically provide estimates of support of tree nodes based on characters but do not generally take into account the effect of sampling error on the tree topology. Nonetheless, studies of the potential of different FDMs as proxies for phylogenetic divergence in modern lineages, such as the present study, provide a framework that may help in modelling the morphological evolution of present and fossil species. 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 93, 813,834. [source]

Is head and neck melanoma a distinct entity?

A clinical registry-based comparative study in 5702 patients with melanoma
Summary Background, The head and neck region is more heavily exposed to ultraviolet (UV) radiation than any other body site. Therefore, cutaneous malignant melanoma (CMM) of the head and neck area is proposed to have notable differences from melanoma at other body sites regarding clinicopathological features and survival of patients. Objectives, The present retrospective study based on clinical registry data aims to compare clinical features and prognostic factors of head and neck melanoma (HNM) vs. melanoma at other anatomical regions (MOR) in order to detect differences which may be associated to the mode of sun exposure. Methods, The clinical records and histopathological findings of 844 patients with clinical stage I and II invasive HNM were compared with the data of 4858 patients with MOR. Survival analysis was performed using the Kaplan,Meier estimate, and the multivariate Cox proportional hazard model was used to evaluate independent prognostic factors. Results, Melanoma density was clearly higher for HNM than for MOR: this was particularly true for the face, where it was elevated by a factor of 26. There was a higher male/female ratio in patients with HNM and they were significantly older than patients with MOR (P < 00001). Breslow tumour thickness did not differ between HNM and MOR. However, CMMs at the scalp were significantly thicker and to a higher degree ulcerated. Concerning clinicopathological CMM subtypes, there was an increased proportion of lentigo maligna melanoma among HNM and of nodular melanoma in the scalp and neck regions. Excision margins were narrower and the rate of complete primary excision was lower in HNM than in MOR. Overall, there was no significant statistical difference in cumulative 10-year survival rates according to Kaplan,Meier estimates among patients with HNM (846%) and MOR (878%). Tumour thickness turned out to be the variable with the highest prognostic impact followed by ulceration in both HNM and MOR. Conclusions, In relation to the skin surface significantly more CMMs were found in the head and neck area than in other anatomical regions. This might indicate, but does not prove, that UV exposure promotes the development of CMM. Although HNM showed specific clinicopathological features, prognosis remained unaffected. Thus HNM seems not to be a distinct subtype of CMM. [source]