基于地形因子的河北省北柴胡生态适宜性区划研究

通过北柴胡中柴胡皂苷类成分含量与地形因子之间的关系,对河北省北柴胡的地形适宜性进行区划研究,为选取种植柴胡的合理区域提供科学的依据。在对河北省43个产地的柴胡实地采样的基础上,应用统计分析方法全面分析了不同地形因子条件下柴胡中柴胡皂苷类成分含量的差异,海拔、坡度、坡向对柴胡皂苷类成分含量的影响,并依据柴胡皂苷类成分与地形因子之间的关系,应用Arc GIS进行了基于地形因子的河北省北柴胡生态适宜性区划。最适宜柴胡皂苷类成分积累的地形因素为海拔(600 m以上)、坡度(4.00~5.50°)、坡向(阳坡),因此,将北柴胡种植在太行山、燕山等地形条件相似的山区地带最为适宜。     

hox gene expression predicts tetrapod-like axial regionalization in the skate,Leucoraja erinacea

The axial skeleton of tetrapods is organized into distinct anteroposterior regions of the vertebral column (cervical, trunk, sacral, and caudal), and transitions between these regions are determined by colinear anterior expression boundaries of Hox5/6, -9, -10, and -11 paralogy group genes within embryonic paraxial mesoderm. Fishes, conversely, exhibit little in the way of discrete axial regionalization, and this has led to scenarios of an origin of Hox-mediated axial skeletal complexity with the evolutionary transition to land in tetrapods. Here, combining geometric morphometric analysis of vertebral column morphology with cell lineage tracing of hox gene expression boundaries in developing embryos, we recover evidence of at least five distinct regions in the vertebral skeleton of a cartilaginous fish, the little skate (Leucoraja erinacea). We find that skate embryos exhibit tetrapod-like anteroposterior nesting of hox gene expression in their paraxial mesoderm, and we show that anterior expression boundaries of hox5/6, hox9, hox10, and hox11 paralogy group genes predict regional transitions in the differentiated skate axial skeleton. Our findings suggest that hox-based axial skeletal regionalization did not originate with tetrapods but rather has a much deeper evolutionary history than was previously appreciated.

The axial skeleton (vertebrae and ribs) is a defining feature of the vertebrate body form, and the existence of distinct axial skeletal regions along the anteroposterior (AP) axis of the body is thought to have facilitated evolutionary radiations and ecological specializations across vertebrate phylogeny (1–3). Tetrapod vertebral columns include at least four axial regions: cervical, trunk (further divided into thoracic and lumbar in most mammals and some reptiles), sacral, and caudal, the lengths of which have been modified in different tetrapod groups to suit various ecologies and lifestyles. In mammals and birds, vertebral regions are patterned by Hox gene expression within the paraxial mesoderm, and experimental manipulations to anterior Hox expression boundaries result in corresponding shifts in vertebral regional boundaries (4–8). For example, in mouse, the anterior expression limit of Hox10 genes aligns with the thoracic–lumbar transition, and in Hox10 paralogy group mutants the lumbar vertebrae undergo homeotic transformations to develop ribs, and therefore take on a thoracic identity (5). Additional comparative gene expression studies indicate that this role for Hox genes in patterning axial skeletal regions is likely conserved across tetrapods (9–14).In contrast, the vertebral skeletons of fishes are thought to be less regionalized than those of tetrapods. Historically, the axial skeletons of both bony and cartilaginous fishes were simply subdivided into trunk and tail regions (15–17), but ostariophysan teleosts also possess a Weberian apparatus, a set of specialized anterior vertebrae that transmit sound from the swim bladder to the inner ear (18). Variation in vertebral morphology along the axis, resulting in up to five regions, has also been documented in several actinopterygian species, including chinook salmon (Oncorhynchus tshawytscha) (19), ponyfish (Leiognathus equulus) (20), and the fossil Tarrasius problematicus (21), suggesting that axial regionalization might be more widespread among actinopterygians than previously thought.hox expression in the paraxial mesoderm has been examined in two teleost fishes with similar vertebral formulae—zebrafish (Danio rerio) and stickleback (Gasterosteus aculeatus)—and both taxa show nested expression along the AP axis (22, 23). In zebrafish, hox expression is initially dynamic but stabilizes at the 20-somite stage (22, 24). In both zebrafish and stickleback, the anterior limit of hoxc6 expression appears to mark the transition to the first rib-bearing vertebra, and in zebrafish the transition from rib-bearing to hemal arch-bearing (i.e., trunk to tail) vertebrae correlates with the anterior expression of hoxa12 (22, 25). Anterior expression limits of other hox genes from paralogy groups 7 to 11 all align with somites that contribute to the rib-bearing trunk region, however, and have no discrete anatomical correlates (22, 25–27). hox13 paralogs are expressed in the tail bud in zebrafish (28) and mutation of Hoxb13 results in the addition of two caudal vertebrae in mice (29), but there is no evidence relating hox13 expression to morphological changes in the caudal fin vertebrae of teleosts. These studies indicate that, despite evidence of some degree of axial regionalization in actinopterygians, teleost hox gene expression patterns are complex and difficult to relate to changes in vertebral morphology. Within cartilaginous fishes, nested AP hox expression has been demonstrated in the catshark (Scyliorhinus canicula) (30, 31). Moreover, regionalization of the axial skeleton of the thorny skate (Amblyraja radiata) was reported based on discrete morphological characteristics of vertebrae along the AP axis (32). However, evidence linking hox expression boundaries to changes in vertebral morphology along the axis in cartilaginous fishes is lacking. It therefore remains unclear what role Hox genes might have played in the evolution of vertebral complexity.To test whether the tetrapod Hox code—and its role in establishing axial regions within the vertebral skeleton—has a deeper evolutionary origin within vertebrates, we investigated hox gene expression and axial skeletal regionalization in a cartilaginous fish, the little skate (Leucoraja erinacea). As a sister taxon to bony vertebrates, comparative studies of skate development facilitate inference of anatomical and developmental conditions in the last common ancestor of jawed vertebrates, and our previous work on skate axial skeletal development allows us to confidently relate somite to vertebral identity along the AP axis (33–35). Contrary to previous assumptions of relative axial skeletal homogeneity, our quantitative assessment of morphology reveals that the skate vertebral column possesses at least five distinct axial regions, with regional boundaries predicted by tetrapod-like patterns of hox gene expression within embryonic somitic mesoderm. This suggests that core elements of the mechanism governing tetrapod axial skeletal regionalization have been conserved for ∼500 million y from the origin of jawed vertebrates.     

Leapfrog volume thresholds and perioperative complications after radical prostatectomy

BACKGROUND:

The authors explored the effect of Leapfrog volume thresholds (LVTs) on 5 short‐term radical prostatectomy (RP) outcomes.

METHODS:

Within the Health Care Utilization Project Nationwide Inpatient Sample (NIS), the authors focused on RPs performed within the 7 most contemporary years (2001‐2007). They tested rates of in‐hospital mortality, intraoperative complications, postoperative complications, and blood transfusions as well as the mean length of stay (LOS), stratified according to the number of LVTs that were met. Multivariable regression analyses were adjusted further for potential confounders.

RESULTS:

Overall, 36.2%, 17.3%, 14.9%, 15.7%, 12.9%, and 3% of RPs were performed at institutions that reached 0 LVT, 1 LVT, 2 LVTs, 3 LVTs, 4 LVTs, and 5 LVTs, respectively. Relative to patients who underwent RP at institutions that reached 0 LVTs, patients who underwent RP at institutions that reached 5 LVTs had fewer comorbidities, were younger, were more likely to hold private insurance, and were more likely to undergo concomitant pelvic lymphadenectomy (all P < .001). In multivariable analyses adjusted for hospital volume (HV), age, race, year of surgery, Charlson Comorbidity Index, hospital region and location, pelvic lymphadenectomy, and insurance status, LVT status was related inversely to LOS and the likelihood of receiving blood transfusions (both P < .001).

CONCLUSIONS:

The current results indicated that LVTs can provide a highly accurate prediction of the probability of 2 important, detrimental, short‐term outcomes after RP, even after accounting for HV. The benefit at institutions that meet LVTs may exceed that at other institutions when short‐term RP outcomes are considered. This observation should be taken into consideration when treatment decisions are made, especially because most RPs were performed at institutions that did not meet any LVTs. Cancer 2012. © 2012 American Cancer Society.     

Perinatal legislative policies and health outcomes

Perinatal epidemiology examines the variation and determinants of pregnancy outcomes from a maternal and neonatal perspective. However, improving public and population health also requires the translation of this evidence base into substantive public policies. Assessing the impact of such public policies requires sufficient data to include potential confounding factors in the analysis, such as coexisting medical conditions and socioeconomic status, and appropriate statistical and epidemiological techniques. This review will explore policies addressing three areas of perinatal medicine—elective deliveries prior to 39 weeks’ gestation; perinatal regionalization; and mandatory paid maternity leave policies—to illustrate the challenges when assessing the impact of specific policies at the patient and population level. Data support the use of these policies to improve perinatal health, but with weaker and less certain effect sizes when compared to the initial patient-level studies. Improved data collection and epidemiological techniques will allow for improved assessment of these policies and the identification of potential areas of improvement when translating patient-level studies into public policies.     

Development of tyrosine hydroxylase-immunoreactive cell populations and fiber pathways in the brain of the dogfish Scyliorhinus canicula: New perspectives on the evolution of the vertebrate catecholaminergic system

Developmental studies of the central catecholaminergic (CA) system are essential for understanding its evolution. To obtain knowledge about the CA system in chondrichthyans, an ancient gnathostome group, we used immunohistochemical techniques for detecting tyrosine hydroxylase (TH), the initial rate‐limiting enzyme of the CA synthesis, to study: 1) the neuromery of developing TH‐immunoreactive (ir) neuronal populations, 2) the development of TH‐ir innervation, and 3) the organization of TH‐ir cells and fibers in the brain of postembryonic stages of the shark Scyliorhinus canicula. The first TH‐ir cells appeared in the hypothalamus and rostral diencephalon (suprachiasmatic, posterior recess and posterior tubercle nuclei at embryonic stage 26, and dorsomedial hypothalamus at stage 28); then in more caudal basal regions of the diencephalon and rostral mesencephalon (substantia nigra/ventral tegmental area); and later on in the anterior (locus coeruleus/nucleus subcoeruleus) and posterior (vagal lobe and reticular formation) rhombencephalon. The appearance of TH‐ir cells in the telencephalon (pallium) was rather late (stage [S]31) with respect to the other TH‐ir prosencephalic populations. The first TH‐ir fibers arose from cells of the posterior tubercle (S30) and formed recognizable ascending (toward dorsal and rostral territories) and descending pathways at S31. When the second half of embryonic development started (S32), TH‐ir fibers innervated most brain areas, and nearly all TH‐ir cell groups of the postembryonic brain were already established. This study provides key information about the evolution of the developmental patterns of central CA systems in fishes and thus may help in understanding how the vertebrate CA systems have evolved. J. Comp. Neurol. 520:3574–3603, 2012. © 2012 Wiley Periodicals, Inc.     

Perinatal care in Portugal: effects of 15 years of a regionalized system

AIM: To share information on the organization of perinatal care in Portugal. METHODS: Data were derived from the Programme of the National Committee for Mother and Child Health 1989, National Institute for Statistics, and Eurostat. RESULTS: In 1989, perinatal care in Portugal was reformed: the closure was proposed of maternity units with less than 1500 deliveries per year; hospitals were classified as level I (no deliveries), II (low-risk deliveries, intermediate care units) or III (high-risk deliveries, intensive care units), and functional coordinating units responsible for liaison between local health centres and hospitals were established. A nationwide system of neonatal transport began in 1987, and in 1990 postgraduate courses on neonatology were initiated. With this reform, in-hospital deliveries increased from 74% before the reform to 99% after. Maternal death rate decreased from 9.2/100,000 deliveries in 1989 to 5.3 in 2003 and, in the same period, the perinatal mortality rate decreased from 16.4 to 6.6/1000 (live births + stillborn with > or = 22 wk gestational age), the neonatal mortality rate decreased from 8.1 to 2.7/1000 live births, and the infant mortality rate from 12.2/1000 live births to 4/1000. CONCLUSION: Regionalization of perinatal care and neonatal transport are key factors for a successful perinatal health system.     

Intra- or extrauterine transport? Comparison of neonatal outcomes using a logistic model

In a retrospective study a comparative analysis of mortality by way of transport (maternal, neonatal, or not referred) was performed on 163 liveborn newborns with a gestational age of less than 32 wk or a birth weight of less than 1500 g. The occurrence of potential mortality risk factors in the subgroups was taken into account. Of these, caesarean section, sex, Apgar score, intubation after delivery, birth weight and gestational age showed a relationship with mortality.

Logistic regression analysis regarding the relationship between mortality and way of transport revealed that mortality in the neonatal transport group was significantly higher than in the maternal transport group, taking into account the confounding risk factors sex, caesarean section, fetal growth retardation, birth weight and gestational age.     

The capital decision-making process in regionalized public health systems: some evidence from Sweden and Denmark

This paper evaluates health capital policy in two regionally structured delivery systems, those of Sweden and Denmark. After a short overview of each nation's health care system, the paper examines the decision-making process for capital equipment and major capital construction in each country. By comparing aspects of system design and subsequent policy outcome, the paper highlights the degree to which capital policy can vary within an apparently similar regionalized framework.