Connections of the representational area of the distal section of the forelimb in the rat sensorimotor cortex

Using horseradish peroxidase, studies have been made on the distribution of retrogradely labeled nervous cells in the sensorimotor cortex of rats. The enzyme was injected into electrophysiologically identified zone of representation of the distal part of the forelimb in areas S2 and S1. It was found that this zone in S2 contains afferent connections mainly from representation of the same extremity in S1 and only a few afferents from other areas of S1, S2 and M1 of the same hemisphere. Single labeled neurones were found in areas S2, S1 and M1 of the contralateral hemisphere. Representation of the forelimb in S1 receives mainly cortical afferents from the same region of S1 and from single cells of homologous zones S2 of the same and S1 of the contralateral hemisphere. Connections from S1 to S2 are more numerous than the opposite ones. In contrast to cats and monkeys, in rats afferent cortical fibers to zone S2 pass not only from the third layer, but also from the fifth and sixth layers of the cortex. It is suggested that during progressive development of the neocortex in mammals, the increase in the degree of separation of neurones (which give origin to corticofugal and cortical connections) among different layers of the cortex takes place.     

Alterations in the human immune response to the hepatitis B vaccine among the elderly

The specific binding of hepatitis B (HBs) antigen by lymphocytes from old people immunized with hepatitis B vaccine was explored. For that purpose HBs antigen was combined with fluorescent microspheres, and labeled antigen was allowed to react with lymphocytes from HBs vaccine-responsive or unresponsive people. Lymphocytes from 10 responders and 14 nonresponders were tested for their antigen-binding ability. For controls, lymphocytes were incubated with microspheres bearing human albumin. Lymphocytes from 8 out of 10 responders were able to recognize HBs antigen; for the nonresponders the ratio was 9 out of 14. HBs-binding lymphocytes were B cells but not T lymphocytes. B and T cells from responders and nonresponders were combined and cultivated for 8 days in the presence of HBs antigen, and antibody-producing cells were counted. Neither B cells alone nor B cells plus T cells from nonresponders were able to produce antibody. On the other hand B cells from unresponsive old people produced antibodies when they were cultivated in the presence of HBs antigen and T cells from responsive old people. These data suggest that some elderly individuals who do not produce antibody after in vivo immunization by HBs vaccine do have antibody-producing cells. Instead of a gap in their immune repertoire, these people are suffering from immune dysfunction.     

Studies of the distribution of the Z-pinch radiance during the implosion of wire arrays in the angara-5-1 facility

Results are presented from time-integrated measurements of soft X-ray emission from Z-pinches during the implosion of simple and nested wire arrays. The blackening density distribution obtained with the help of a pinhole camera is recalculated into the time-integrated Z-pinch radiance. It is found that, in the case of a simple wire array, up to 70% of the total SXR energy emitted during a discharge is radiated from the axial region, the rest of energy being radiated from plasma jets, whereas in the case of a nested wire array, more than 90% of the SXR energy is radiated from the axial region.     

A Note on the Relevance of the Mesocotyl in the Systematics of the Gramineae

Seedlings of most of the Gramineae possess a mesocotyl, buta few tribes are characterized by its absence. Seedlings ofBromus resemble the Triticeae in having no mesocotyl and thisis further evidence for separating the Bromeae both from theFestuceae and from the Brachypodiae.     

Main traits of the annual cycles of the fleas (Aphaniptera) of the mountain suslik in the Baksan River valley

Data are given on the fleas of Citellus musicus from Central Caucasus. Ecological peculiarities of fleas from the above region were compared with data known for fleas from plain Precaucasus. Differences between annual cycles of fleas of the same species from two altitude belts of the Baksan valley are considered. Epizootological significance of ecological peculiarities of fleas in the Baksan plague nidus is discussed.     

Rostrocaudal Somatotopy in the Neural Connections Between the Lateral Hypothalamus and the Dorsal Periaqueductal Gray of the Rat Brain

Summary 1. The lateral hypothalamus (LH) and the dorsal periaqueductal gray area (dPAG) are two important brain structures involved in central cardiovascular control.2. In the present study, we searched for possible rostrocaudal somatotopy in the neural connections from the three subdivisions of the LH (anterior—LHa; tuberal—LHt and posterior—LHp) to the different rostrocaudal portions of the dPAG.3. The bidirectional neuronal tracer biotinylated-dextran-amine (BDA) was microinjected into different rostrocaudal coordinates of the dPAG (AP 3.4–2.7 mm) of male Wistar rats. One week later, animals were sacrificed and brain slices were processed and analyzed to detect neuronal efferent projections from the LH to the dPAG.4. Neuronal cell body staining was observed along all the rostrocaudal axis of the LH when BDA was microinjected in more rostral dPAG coordinates. When the BDA was microinjected into more caudal dPAG regions, labeled neurons were observed only in the caudal portion of the LH.5. Efferent projections from the LHa were directed only to the rostral portion of the dPAG. Projections from the rostral and medial portions of the LHt were also directed to the rostral dPAG, whereas both rostral and caudal dPAG received projections from the caudal portion of the LHt. Efferent projections from the anterior portion of the LHp were directed to both rostral and caudal dPAG, whereas projections from the caudal LHp were only directed to the rostral portion of the dPAG.6. The results suggest a somatotopic correlation in LH projections to the dPAG with main connections to the rostral dPAG, which are efferent from the three divisions of the LH. More caudal regions of the dPAG received afferents only from posterior sites in the LH.7. Moreover, the results point out to extensive and complex neural somatotopic projections from all LH subdivisions to different rostrocaudal portions of the dPAG, reinforcing the idea of significant functional interactions between the brain structures.     

Further data on the origin of gonadotropin releasing hormone in the median eminence of the rat hypothalamus

Gonadotropin releasing hormone (GnRH) content of the two halves of the median eminence of the rat hypothalamus was determined by radioimmunoassay three weeks after three different unilateral knife cuts around the preoptic area. A unilateral cut in front or above the area caused a more than 25% decrease in the GnRH content of the two halves of the median eminence. A cut lateral to the preoptic region had only a slight effect similar to that observed after sham operations. The data suggest that probably more than 50% of the rat median eminence GnRH derives from outside the preoptic-suprachiasmatic region. The GnRH fibres projecting to the median eminence but arising from outside the preoptic region, probably mainly from GnRH perikarya in the limbs of the diagonal band of Broca and septum, enter this area partly from rostral and partly from above, but not from lateral direction. partly from rostral and partly from above, but not from lateral direction. Several of these fibres probably cross before terminating in the median eminence.     

Effect of deafferentation of the forelimb on the postnatal development of the synaptic plasticity in the hippocampus

The postnatal development of LTP in CA1 area of hippocampus was studied in hippocampal slices from 13-20-day-old intact rats, after unilateral resection of n. medianus on the 13th day, and sham-operated animals. In slices from the intact rats prepared on the 15th-16th-day of postnatal development, the LTP magnitude and duration were significantly larger than in adult animals. Partial deafferentation eliminated this overshoot. However, a less pronounced increase in synaptic plasticity was observed in operated animals on the 17th day. The LTP suppression in the experimental animals may be explained by a decrease in the NMDA receptor activity due to enhanced synaptic activity in the hippocampus. We think that the limited sensory inflow from the partially deafferented forelimb to the hippocampus via the entorhinal cortex may be compensated by activation of other inputs from specific or/and nonspecific pathways. In contrast, the LTP magnitude and duration were significantly increased in slices from the sham-operated rats. This increase may be explained by a decline of synaptic activation of the hippocampus under anesthesia.     

Differences in the concentration of erythrocytes and the hematocrit value in the blood in relation to the location of the vessels and the intensity of the blood flow

The experiments in adult rabbits revealed that in the blood flowing in cerebral veins the red cell concentration and hematocrit are much greater than in the veins of hind legs of the same animals. In blood samples taken from the heart these values are higher than in those taken from the hind leg, but usually lower than in blood samples taken from the brain. Under conditions of reduced cerebral blood flow (ischemia) the red cell concentration and hematocrit in the brain vessels decrease significantly as compared to the control conditions. Thus, the red cell distribution in arterial branching sequence is irregular, depending both on the localization of the vascular bed and the blood flow rate in it.     

Modeling the hazard of transition into the absorbing state in the illness-death model

The illness-death model is the simplest multistate model where the transition from the initial state 0 to the absorbing state 2 may involve an intermediate state 1 (e.g., disease relapse). The impact of the transition into state 1 on the subsequent transition hazard to state 2 enables insight to be gained into the disease evolution. The standard approach of analysis is modeling the transition hazards from 0 to 2 and from 1 to 2, including time to illness as a time-varying covariate and measuring time from origin even after transition into state 1. The hazard from 1 to 2 can be also modeled separately using only patients in state 1, measuring time from illness and including time to illness as a fixed covariate. A recently proposed approach is a model where time after the transition into state 1 is measured in both scales and time to illness is included as a time-varying covariate. Another possibility is a model where time after transition into state 1 is measured only from illness and time to illness is included as a fixed covariate. Through theoretical reasoning and simulation protocols, we discuss the use of these models and we develop a practical strategy aiming to (a) validate the properties of the illness-death process, (b) estimate the impact of time to illness on the hazard from state 1 to 2, and (c) quantify the impact that the transition into state 1 has on the hazard of the absorbing state. The strategy is also applied to a literature dataset on diabetes.     

Second messengers involved in the muscarinic control of the heart: the role of the phosphoinositide response

Two heart muscarinic responses are compared, the reduction of cyclic AMP concentration and the hydrolysis of phosphoinositides. It is suggested that the former is more important physiologically, since the latter is a slow response requiring much higher agonist concentrations. Inositol trisphosphate released from phosphoinositides is unlikely to produce a positive inotropic effect by releasing calcium from the sarcoplasmic reticulum. However, long term muscarinic effects may involve activation of protein kinase C by diacylglycerol released from phosphoinositides.     

Spermatozoa transport in the oviduct of the chicken and the turkey

Recent studies of the storage and release of spermatozoa from utero-vaginal glands in birds have shown that: following intra-vaginal insemination, storage is completed within 2-3 d (domestic hen) or 1-5 d (turkey) and not within a few minutes or hours as previously described; as spermatozoa can be recovered from any segment of the oviduct during the egg formation cycle, it seems unlikely that sperm release from the utero-vaginal glands is directly dependent upon the egg formation cycle. The progressive inability of spermatozoa to agglutinate may be part of this mechanism.     

Differential localization of glycoconjugates having affinity for concanavalin A on the surface of the sperm head in the testis, the epididymis, and the ejaculate of the ram

The localization of Con A receptors on the surface of the head of ram spermatozoa originating from the rete testis, from three regions of the epididymis, or from the ejaculate was investigated using a gold-Con A labelling technique. Electron microscopic observation revealed three major localizations, each being characteristic of the origin of the spermatozoa: periacrosomal in the rete testis, postacrosomal in the epididymis, on the entire surface of the sperm head in the ejaculate.     

Aneurysm of the abdominal aorta: the prognosis of the condition if untreated

In a study of the autopsies of 87 patients at Cedars of Lebanon and Los Angeles County General hospitals, it was noted that 38 had died from rupture of the aneurysm and 49 had died of unrelated diseases, the aneurysm being intact postmortem. At each age group from 50 to 85 years, just as many patients who had the lesion died from rupture of the aneurysm as from other causes. It was found that predisposing to rupture of the aneurysm was not the age of the patient, not hypertension, but definitely the size of the aneurysm. Aneurysms under 6 cm. in diameter (most are visible by x-ray) rarely ruptured.     

Brachyury, the blastopore and the evolution of the mesoderm

The role of Brachyury and other T-box genes in the differentiation of mesoderm and endoderm of vertebrates is well established. Recently, homologues of Brachyury have been isolated from an increasing number of diverse organisms ranging from Cnidaria to vertebrates and insects. Comparative expression and function analysis allows the origin of the mesoderm and the evolution of the developmental role of Brachyury gene family in metazoans to be traced. The data suggest that an ancestral function of Brachyury was to designate a blastoporal region that had distinct properties in induction and axis elongation. A subset of blastoporal cells expressing Brachyury and other genes that convey specific mesodermal functions may have segregated as a distinct cell population from this region in the course of mesoderm evolution.     

Exophthalmos from the standpoint of the ophthalmologist

There are many causes of abnormal protrusion of one or both eyes, the most common of which is imbalance of the glands of internal secretion. Among other causes are a variety of tumors that originate behind the eye or that extend to that location from other parts in the body. Infections can extend to the orbit behind the eye from the neighboring structures such as the paranasal sinuses. Infection may also extend to the orbit from distant areas by way of the blood and cause exophthalmos.     

长江朱杨江段和沱江富顺江段鱼类体内16种多环芳烃的含量

于2010年9-11月在长江朱杨江段采集到9种鱼类标本, 分别为瓦氏黄颡鱼(Pelteobagrus vachelli Richardson)、圆筒吻 (Rhinogobio cylindricus Gnther)、鲤(Cyprinus carpio Linnaeus)、鲫(Carassius auratus Linnaeus)、大眼鳜(Siniperca kneri Garman)、铜鱼(Coreius heterodon Bleeker)、圆口铜鱼(Coreius guichenoti Sauvage et Dabry)、大鳍鳠(Mystus macropterus Bleeker)和鲇(Silurus asotus Linnaeus); 在该江段上游支流沱江富顺江段采集到6种鱼类标本, 分别为鲫、黄颡鱼(Pelteobagrus fulvidraco Richardson)、鲤、大眼鳜、大鳍鳠和鲇, 每种鱼的样本量为6-11尾, 共计192尾。采用快速溶剂萃取及气相色谱法对鱼体中的16种多环芳烃(PAHs)含量进行了检测。结果显示, 在两个江段的各种鱼体样本中均检测到了多种多环芳烃的存在。在长江干流朱杨江段所采集到的9种鱼中瓦氏黄颡鱼体内多环芳烃总量(PAHs)最高, 其含量为(2803.78 215.37) ng/g; 鲇鱼体内PAHs最低, 其含量为(515.8638.80) ng/g。在沱江富顺江段采集到的6种鱼中鲫体内PAHs最高, 为(8498.571128.22) ng/g; 鲇鱼体内PAHs最低, 其含量为(1295.0569.69) ng/g。采集自长江朱杨段和沱江富顺段两采集地的相同种类有5种, 富顺段5种鱼体内PAHs均高于朱杨段同种类鱼体内的含量; 除大眼鳜外, 其余4种鱼的差异均达到显著水平。富顺江段鱼类体内高分子量多环芳烃比例较高, 而朱杨江段鱼类体内富集的低分子量多环芳烃和中分子量多环芳烃的比例较高。通过讨论认为, 长江朱杨段及其支流沱江富顺段的鱼体均受到了多环芳烃的污染, 并且沱江鱼类受多环芳烃的污染程度高于长江干流朱杨段鱼类。此外, 沱江富顺段鱼体所含的高分子量多环芳烃组成百分比高于长江干流朱杨段的鱼体, 但其中、低分子量多环芳烃组成百分比相对于干流鱼类较低, 可能的原因是两个江段多环芳烃的污染源不同。       

Frequency of the stages in the cycle of the seminiferous epithelium in the rat

This study determined the optimum number of tubules to be counted per testis cross section, and the number of animals per treatment group, when changes in stage frequencies in the cycle of the seminiferous epithelium are criteria for assessing effects of treatment on spermatogenesis. A data base of 9,672 observed and staged tubules was collected from testicular cross sections of 15 Sprague-Dawley rats. A significant variation between animals was found for the frequencies of Stages I, II, IV, VI, VIII, and XIII. Computer simulation was used to randomly select different combinations of animal and tubule numbers from the observed data. Stage frequency means from each simulation experiment were compared statistically to observed mean frequencies. A model that used data from all 14 stages was analyzed. The following conclusions were made: a) a minimum of 200 tubule cross sections/testis is recommended for estimating stage frequencies; b) for a fixed number of tubules scored, the number of animals sampled is more important than the number of tubules per animal in reducing variance; c) to detect a difference of 2 standard deviations from the mean with a 2% error rate and examining 200 tubules/testis, at least 12 animals must be used per group when assessing all 14 stages; d) when individual stages are examined using 10 animals per group, only Stage VII has 80% or greater power of test (alpha = 0.05) to detect a frequency difference; e) pooling stages into 3-4 groups is recommended to improve the power of detecting a treatment difference.     

各型肝病患者红细胞内氨基酸检测的临床研究

本文对３０例正常人和１０８例各型肝病患者红细胞内氨基酸进行检测,结果显示,各型肝炎与正常人比较红细胞内氨基酸均表现不同程度的增高和降低。如正常人红细胞内１７种氨基酸的总量为３５５４．４７μｍｏｌ／Ｌ,支／芳比值３．０６±０．４０;急性肝炎总量３４２３．２５μｍｏｌ／Ｌ,支／芳比值２．４８±０．３０;慢性肝炎（轻度）总量３３２９．３３μｍｏｌ／Ｌ,支／芳比值２．３９±０．２２;慢性肝炎（中度）总量３２１９．３２μｍｏｌ／Ｌ,支／芳比值１．８３±０．４０;肝硬化总量３７６２．３３μｍｏｌ／Ｌ,支／芳比值１．３６±０．４１。