One is the loneliest number: A review of the ganglion impar and its relation to pelvic pain syndromes

The ganglion impar is often overlooked as a component of the sympathetic nervous system. Despite its obscurity, this ganglion provides a pathway for neurons by accommodating postganglionic sympathetics, visceral afferents, and somatic fibers traveling to and from the pelvis. Its classic anatomic location as described in the 1720's held up until recently, with the current literature now revealing a great deal of anatomical variability. This variation becomes important when the ganglion impar is used as a treatment target for patients with chronic pelvic pain – its primary clinical implication. The aim of this review was to provide a better understanding of the anatomy of ganglion impar, accounting for variation in size, shape, and location. In addition, the clinical importance and treatment modalities associated with the ganglion impar are outlined. Clin. Anat. 26:855–861, 2013. © 2013 Wiley Periodicals, Inc.     

The social re-orientation of adolescence: a neuroscience perspective on the process and its relation to psychopathology

BACKGROUND: Many changes in social behavior take place during adolescence. Sexuality and romantic interests emerge during this time, and adolescents spend more time with peers and less time with parents and family. While such changes in social behavior have been well documented in the literature, relatively few neurophysiological explanations for these behavioral changes have been presented. METHOD: In this article we selectively review studies documenting (a) the neuronal circuits that are dedicated to the processing of social information; (b) the changes in social behavior that take place during adolescence; (c) developmental alterations in the adolescent brain; and (d) links between the emergence of mood and anxiety disorders in adolescence and changes in brain physiology occurring at that time. RESULTS: The convergence of evidence from this review indicates a relationship between development of brain physiology and developmental changes in social behavior. Specifically, the surge of gonadal steroids at puberty induces changes within the limbic system that alters the emotional attributions applied to social stimuli while the gradual maturation of the prefrontal cortex enables increasingly complex and controlled responses to social information. CONCLUSIONS: Observed alterations in adolescent social behavior reflect developmental changes in the brain social information processing network. We further speculate that dysregulation of the social information processing network in this critical period may contribute to the onset of mood and anxiety disorders during adolescence.     

Experimental intestinal malabsorption states and their relation to clinical syndromes

Summary The literature pertaining to experimental malabsorption syndromes induced in laboratory animals is reviewed and the relationships between these syndromes and human malabsorption are discussed. Particular attention is paid to functional studies and to relationships between structure and function. The syndromes discussed include the effect of anti-mitotic drugs, including colchicine (which may have a distinct inhibitory effect on intestinal disaccharidases and therefore provide a mode for disaccharide intolerance); the effect of ionising radiation; intestinal damage from triparanol, and its relationship to human gluten enteropathy; the response of the intestine to ischaemia and shock; and finally the effect of neomycin, a drug that has provoked symptoms of malabsorption in man which have never been satisfactorily explained nor reproduced in animal studies.     

金仓鼠卵巢囊及卵巢囊淋巴孔的研究进展

卵巢系膜（ｍｅｓｏｔｕｂａｒｉｕｍ　ｓｕｐｅｒｉｕｓ,　ＭＴＳ）的发展程度有很大的种属差异。大多数啮齿类的卵巢系膜高度发展形成一个（几乎）完全闭口、包裹卵巢的囊,这个囊称卵巢囊（ｏｖａｒｙ　ｂｕｒｓａ）。淋巴孔是毛细淋巴管在间皮面的微小开口。金仓鼠的卵巢囊围绕卵巢形成完全的包裹,并且其内壁存在卵巢囊淋巴孔。本文综述了金仓鼠卵巢囊的形态结构、出生后卵巢囊及囊腔的发育以及卵巢囊淋巴孔的形态、功能,囊腔内液的引流等研究结果。     

Involution of the chicken bursa of Fabricius: a light microscopic study with special reference to transport of colloidal carbon in the involuting bursa

The involution of the bursa of Fabricius in White Leghorn chickens and the transport of colloidal carbon in the involuting bursa were studied on light microscopy. In chickens, from newly hatched to 23.5 weeks of age, the bursa was weighed, its histology was described, and the mitoses in the cortical and medullary compartments of the lymphoid follicles were counted. Decrease in bursal weight and in the number of mitoses were observed between 10 and 16 weeks of age. During week 17.5, the follicle-associated epithelium began to lose its endocytic capability, and mucin droplets appeared in the follicular medulla initiating the large mucoid cysts that were seen in the later phases of involution. The involutionary process was almost completed by week 23.5, when the bursa appeared as a fibrotic residue without intact lymphoepithelial structures. The particulate tracer used, colloidal carbon, was not observed to be transported to other organs from the bursa. The present study gives further support to the idea that after completing its central immune function in 6 weeks [21] the bursa, as estimated histologically, still possesses capacity to function like a peripheral lymphoid organ until 16 weeks of age.     

Physiology: Utero-cervical inhibitory reflex. The description of a reflex and its clinical significance

The functional relationship of the uterine corpus to the cervixwas studied in 14 healthy women. The uterus was stimulated byan electro-myographic (EMG) needle electrode and the cervicalpressure recorded by a balloon-tipped catheter. The test wasrepeated in seven women after the uterus had been anaesthetized.In the other seven patients, the response of both the uterineEMG and pressure to cervical dilatation was registered. TheEMG needle electrode was then inserted into the cervix and theuterine pressure response to both stimulation and dilatationof the non-anaesthetized and anaesthetized cervix was recorded.Uterine muscle stimulation led to a cervical pressure drop froma mean of 15.8± 6.6 to 5.3 ± 2.2 cm H₂O (P<0.01). The cervical pressure did not respond to stimulationof the anaesthetized uterus. Cervical dilatation caused increaseof the uterine pressure from a mean of 16.2± 5.2 to 42.8± 10.5 cm H2O (P< 0.01), whereas cervical stimulationeffected a uterine pressure drop to a mean of 3.6 ± 1.8cm H₂O (P< 0.01). Stimulation or dilatation of the anaesthetizedcervix did not cause uterine pressure changes. The invariablecervical dilatation upon uterine stimulation suggests a reflexrelationship which we have named ‘utero-cervical inhibitoryreflex’ (UCIR). It seems that the reflex comes into actionduring labour and in conditions of uterine retention of bloodor a dead ovum. Its impairment may interfere with cervical dilatationor lead to cervical incompetence. The UCIR could be includedas an investigative tool in utero-cervical disorders.     

The inheritance of sinking-pre-beta lipo-protein and its relation to the Lp(a) antigen*

We have investigated the genetics of plasma sinking-pre-beta lipoprotein (spβ) as determined by the method of Breckenridge and Maguire, using several approaches: (i) a population study, (ii) a twin study and (iii) the use of family data. In addition, by the use of split samples, the spβ level as determined by us was correlated with Lp(a) typing carried out in Oslo by Dr. Kåre Berg. Although the spβ level is a continuous character, the results clearly showed it to be to a considerable extent under the control of the major autosomal gene pair constituted by the alleles Lp^a and Lp, which mainly control the production of the Lp(a) antigen, Lp^a being dominant. In our data the boundary between the LpLp and Lp^a Lp genotypes appeared to fall between the spβ 2 and 3 mg% levels, while that between Lp^a Lp and Lp^a Lp^a was in the 15 mg% region. These boundaries, which were inferred from both typing and population statistics, received good confirmation from the family data. It appears that some 88% of the variation in spp level is directly ascribed to segregation of Lp^a and Lp. On the basis of the twin study and other data, we conclude that the residual observed variation in spβ is almost entirely ascribed to analytical error of determination and polygenic effects, the influence of environment being negligible. The heritability is close to 100%.     

The trochlear nerve of amphibians and its relation to proprioceptive fibers: a qualitative and quantitative HRP study

Summary The cells of origin of the trochlear nerve of urodeles, anurans and gymnophionans were labelled with HRP in order to compare the location and morphology of trochlear motoneurons and to find evidence for sensory fibers in the trochlear nerve of amphibians. Trochlear motoneuron perikarya were found in a ventral tegmental position predominantly on the contralateral side, but an ipsilateral cell was present in some specimens of urodeles and anurans. About 19 motoneurons were labelled inAmbystoma, about 60 motoneurons inXenopus, and a maximum of 7 cells inIchthyophis. Decussation of trochlear nerve fibers showed only inXenopus a highly variable pattern.In urodeles, selective filling of the trochlear nerve labelled in addition to trochlear motoneurons a caudo-medial tectal group of about 20 neurons of the nucleus of the mesencephalic root of the trigeminal nerve. Gymnophionans showed also labelled cells of the mesencephalic trigeminal root in the caudal midbrain close to the trochlear nerve root. In some frogs, a few cells of the mesencephalic trigeminal root were labelled in the caudal tectum and occasionally in the velum medullare anterius.Comparison of the numbers of trochlear nerve fibers with HRP-labelled motoneurons revealed inXenopus a proportion of 1.2:1, but of 2.7:1 inAmbystoma. However, counting both labelled motoneurons and cells of the mesencephalic trigeminal root resulted in a trochlear nerve fiber to labelled neuron proportion of 1.3:1 inAmbystoma much like inXenopus. The numbers of superior oblique muscle fibers and of trochlear nerve fibers, but not of HRP-labelled motoneurons, increased significantly with size inXenopus laevis. We suggest that increased peripheral branching of individual fibers within the trochlear nerve with size rather than differentiation of additional motoneurons takes place in growing postmetamorphicXenopus.In contrast to other vertebrates studied so far, the trochlear nerve is a mixed nerve inAmbystoma and perhaps inIchthyophis. Whether this reflects a primitive or a derived condition is at present unclear.Abbreviations (nomenclature according to Nikundiwe and Nieuwenhuys 1983 and Opdam and Nieuwenhuys 1976) ap alar plate - av nucleus anteroventralis tegmenti - bp basal plate - flm fasciculus longitudinalis medialis - ip nucleus interpeduncularis - is nucleus isthmi - it isthmic tegmentum - nIV nervus trochlearis - pd nucleus posterodorsalis tegmenti - pr nucleus pretrigeminalis - prm nucleus profundus mesencephali - pv nucleus posteroventralis tegmenti - rm nucleus reticularis medius - rs nucleus reticularis superior - si sulcus isthmi - t teclum mesencephali - tel telencephalon - teg tegmentum mesencephali - ts torus semicircularis - vis n. visceralis secundarius - III third cranial ventricle - IV fourth cranial ventricle