bluuebunny/crossref_metadata_2025 huggingface dataset:
Pleiotropic effects of a rel mutation on stress survival of Rhizobium etli CNPAF512
Authors: Braeken Kristien , Fauvart Maarten , Vercruysse Maarten , Beullens Serge , Lambrichts Ivo , Michiels Jan
Published: December 2008

Background

The rel gene of Rhizobium etli (rel

Ret
), the nodulating endosymbiont of the common bean plant, determines the cellular level of the alarmone (p)ppGpp and was previously shown to affect free-living growth and symbiosis. Here, we demonstrate its role in cellular adaptation and survival in response to various stresses.

Results

Growth of the R. etli rel

Ret
mutant was strongly reduced or abolished in the presence of elevated NaCl levels or at 37°C, compared to the wild type. In addition, depending on the cell density, decreased survival of exponentially growing or stationary phase rel

Ret
mutant cells was obtained after H2O2, heat or NaCl shock compared to the wild-type strain. Survival of unstressed stationary phase cultures was differentially affected depending on the growth medium used. Colony forming units (CFU) of rel

Ret
mutant cultures continuously decreased in minimal medium supplemented with succinate, whereas wild-type cultures stabilised at higher CFU levels. Microscopic examination of stationary phase cells indicated that the rel

Ret
mutant was unable to reach the typical coccoid morphology of the wild type in stationary phase cultures. Assessment of stress resistance of re-isolated bacteroids showed increased sensitivity of the rel

Ret
mutant to H2O2 and a slightly increased resistance to elevated temperature (45°C) or NaCl shock, compared to wild-type bacteroids.

Conclusion

The rel

Ret
gene is an important factor in regulating rhizobial physiology, during free-living growth as well as in symbiotic conditions. Additionally, differential responses to several stresses applied to bacteroids and free-living exponential or stationary phase cells point to essential physiological differences between the different states.
Large-scale preparation of active caspase-3 in E. coli by designing its thrombin-activatable precursors
Authors: Kang Hyo Jin , Lee Young-mi , Jeong Yu-Jin , Park Kyoungsook , Jang Mi , Park Sung Goo , Bae Kwang-Hee , Kim Moonil , Chung Sang J
Published: December 2008

Background

Caspase-3, a principal apoptotic effector that cleaves the majority of cellular substrates, is an important medicinal target for the treatment of cancers and neurodegenerative diseases. Large amounts of the protein are required for drug discovery research. However, previous efforts to express the full-length caspase-3 gene inE. colihave been unsuccessful.

Results

Overproducers of thrombin-activatable full-length caspase-3 precursors were prepared by engineering the auto-activation sites of caspase-3 precursor into a sequence susceptible to thrombin hydrolysis. The engineered precursors were highly expressed as soluble proteins inE. coliand easily purified by affinity chromatography, to levels of 10–15 mg from 1 L ofE. coliculture, and readily activated by thrombin digestion. Kinetic evaluation disclosed that thrombin digestion enhanced catalytic activity (kcat/KM) of the precursor proteins by two orders of magnitude.

Conclusion

A novel method for a large-scale preparation of active caspase-3 was developed by a strategic engineering to lack auto-activation during expression with amino acid sequences susceptible to thrombin, facilitating high-level expression inE. coli. The precursor protein was easily purified and activated through specific cleavage at the engineered sites by thrombin, generating active caspase-3 in high yields.
Trend Inflation, Indexation, and Inflation Persistence in the New Keynesian Phillips Curve
Authors: Cogley Timothy , Sbordone Argia M
Published: December 2008

Purely forward-looking versions of the New Keynesian Phillips curve (NKPC) generate too little inflation persistence. Some authors add ad hoc backward-looking terms to address this shortcoming. We hypothesize that inflation persistence results mainly from variation in the long-run trend component of inflation, which we attribute to shifts in monetary policy. We derive a version of the NKPC that incorporates a time-varying inflation trend and examine whether it explains the dynamics of inflation. When drift in trend inflation is taken into account, a purely forward-looking version of the model fits the data well, and there is no need for backward-looking components. (JEL E12, E31, E52)
Changes in the Consumption, Income, and Well-Being of Single Mother Headed Families
Authors: Meyer Bruce D , Sullivan James X
Published: December 2008

We investigate well-being changes for single mother headed families targeted by recent tax and welfare reforms. Measured income changes sharply differ from consumption changes. We examine disaggregated consumption, time use, and health insurance coverage. Increases in housing and transportation spending mostly account for the rise in consumption in the bottom quintiles. We find modest improvement in housing quality, but the evidence is less strong at the very bottom. The consumption of nonmarket time for those in the bottom half of the consumption distribution falls sharply, indicating a loss in utility for those families if nonmarket time is valued above $3 per hour. (JEL D12, I31, I32, J12, J16)
Negative Impact of Statins on Oligodendrocytes and Myelin FormationIn VitroandIn Vivo
Authors: Klopfleisch Steve , Merkler Doron , Schmitz Matthias , Klöppner Sabine , Schedensack Mariann , Jeserich Gunnar , Althaus Hans H. , Brück Wolfgang
Published: December 2008

Statins are widely prescribed drugs in cardiovascular diseases. Recent studies also demonstrated anti-inflammatory and immunomodulatory properties of statins by modulating the activity of small GTPases. Statins are thus considered as potential therapeutic drug for the inflammatory demyelinating disease multiple sclerosis (MS). However, little is known about the effects of statins on myelin-forming oligodendrocytes. Here, we show that statins hamper process and myelin formationin vitroby interfering with Ras and Rho signaling in mature oligodendrocytes and provide evidence that statins impair ongoing remyelinationin vivo. Our findings may have significant implications for the application of statins in MS patients and in other demyelinating diseases of the CNS.
Medial Prefrontal Cortex Supports Recollection, But Not Familiarity, in the Rat
Authors: Farovik Anja , Dupont Laura M. , Arce Miguel , Eichenbaum Howard
Published: December 2008

There is continuing controversy about the extent to which the rodent medial prefrontal cortical area (mPFC) is functionally homologous to the dorsolateral prefrontal cortex in humans and nonhuman primates. Previous studies have compared the effects of mPFC lesions in rats to those of dorsolateral prefrontal lesions in working memory, strategy switching, and temporal ordering. None, however, has examined the role of the rodent mPFC in recognition memory, wherein, in humans, dorsolateral prefrontal damage results in a deficit in source monitoring resulting in impaired recollection. In the present study, we examined recognition memory in rats with bilateral mPFC lesions (prelimbic/infralimbic regions; ibotenic acid) using a variant of a non-match-to-sample task with manipulations of response bias that allowed for a signal detection analysis that distinguishes recollection and familiarity contributions to recognition memory. Animals with medial prefrontal lesions had a modest overall deficit in recognition with no general change in their tendency to elicit “old” or “new” responses. Signal detection analyses indicated that rats with mPFC damage had a curvilinear and symmetrical receiver operating characteristic (ROC) curve, compared with a curvilinear and asymmetrical ROC curve in control subjects, indicating that mPFC damage severely reduced recollection-based performance, while sparing familiarity. The recollection failure was associated with an impaired ability to reject new items (increased false alarm rate), whereas the identification of old items (hit rate) was normal. This pattern of findings is similar to that observed in humans with dorsolateral prefrontal damage and is complementary to the selective deficit in hit rate observed after hippocampal damage.
Crk and Crk-Like Play Essential Overlapping Roles Downstream of Disabled-1 in the Reelin Pathway
Authors: Park Tae-Ju , Curran Tom
Published: December 2008

Reelin controls neuronal positioning in the developing brain by binding to the two lipoprotein receptors, very-low-density lipoprotein receptor and apolipoprotein E receptor 2, to stimulate phosphorylation of Disabled-1 (Dab1) by the Fyn and Src tyrosine kinases. Crk and Crk-like (CrkL) have been proposed to interact with tyrosine phosphorylated Dab1 to mediate downstream events in the Reelin pathway. However, these adaptor proteins are widely expressed, and they fulfill essential functions during embryonic development. To address their specific roles in Reelin-mediated neuronal migration, we generated mutant mice, by Cre-loxP recombination, lackingCrkandCrkLin most neurons. These animals displayed the major anatomic features ofreelerincluding, cerebellar hypofoliation, failure of Purkinje cell migration, absence of preplate splitting, impaired dendritic development, and disruption of layer formation in the hippocampus and cerebral cortex. However, proximal signaling involving tyrosine phosphorylation and turnover of Dab1 occurred normally in the mutant mouse brain and in primary cortical neurons treated with Reelin. In contrast, two downstream signaling events, Reelin-induced phosphorylation of C3G and Akt, were not observed in the absence of Crk and CrkL in mouse embryonic cortical neurons. These findings place C3G and Akt phosphorylation downstream of Crk and CrkL, which play essential overlapping functions in the Reelin signaling pathway.
Estradiol Modulates Functional Brain Organization during the Menstrual Cycle: An Analysis of Interhemispheric Inhibition
Authors: Weis Susanne , Hausmann Markus , Stoffers Barbara , Vohn René , Kellermann Thilo , Sturm Walter
Published: December 2008

According to the hypothesis of progesterone-mediated interhemispheric decoupling (Hausmann and Güntürkün, 2000), functional cerebral asymmetries (FCAs), which are stable in men and change during the menstrual cycle in women, are generated by interhemispheric inhibition of the dominant on the nondominant hemisphere. The change of lateralization during the menstrual cycle in women might indicate that sex hormones play an important role in modulating FCAs. We used functional magnetic resonance imaging to examine the role of estradiol in determining cyclic changes of interhemispheric inhibition. Women performed a word-matching task, while they were scanned twice during the cycle, once during the menstrual and once during the follicular phase. By use of a connectivity analysis we found that the inhibitory influence of left-hemispheric language areas on homotopic areas of the right hemisphere is strongest during the menses, resulting in a pronounced lateralization. During the follicular phase, due to rising estradiol levels, inhibition and thus functional cerebral asymmetries are reduced. These results reveal a powerful neuromodulatory action of estradiol on the dynamics of functional brain organization in the female brain. They may further contribute to the ongoing discussion of sex differences in brain function in that they help explain the dynamic part of functional brain organization in which the female differs from the male brain.
Cerebrovascular Dysfunction in Amyloid Precursor Protein Transgenic Mice: Contribution of Soluble and Insoluble Amyloid-β Peptide, Partial Restoration via γ-Secretase Inhibition
Authors: Han Byung Hee , Zhou Meng-liang , Abousaleh Fadi , Brendza Robert P. , Dietrich Hans H. , Koenigsknecht-Talboo Jessica , Cirrito John R. , Milner Eric , Holtzman David M. , Zipfel Gregory J.
Published: December 2008

The contributing effect of cerebrovascular pathology in Alzheimer's disease (AD) has become increasingly appreciated. Recent evidence suggests that amyloid-β peptide (Aβ), the same peptide found in neuritic plaques of AD, may play a role via its vasoactive properties. Several studies have examined young Tg2576 mice expressing mutant amyloid precursor protein (APP) and having elevated levels of soluble Aβ but no cerebral amyloid angiopathy (CAA). These studies suggest but do not prove that soluble Aβ can significantly impair the cerebral circulation. Other studies examining older Tg2576 mice having extensive CAA found even greater cerebrovascular dysfunction, suggesting that CAA is likely to further impair vascular function. Herein, we examined vasodilatory responses in young and older Tg2576 mice to further assess the roles of soluble and insoluble Aβ on vessel function. We found that (1) vascular impairment was present in both young and older Tg2576 mice; (2) a strong correlation between CAA severity and vessel reactivity exists; (3) a surprisingly small amount of CAA led to marked reduction or complete loss of vessel function; 4) CAA-induced vasomotor impairment resulted from dysfunction rather than loss or disruption of vascular smooth muscle cells; and 5) acute depletion of Aβ improved vessel function in young and to a lesser degree older Tg2576 mice. These results strongly suggest that both soluble and insoluble Aβ cause cerebrovascular dysfunction, that mechanisms other than Aβ-induced alteration in vessel integrity are responsible, and that anti-Aβ therapy may have beneficial vascular effects in addition to positive effects on parenchymal amyloid.
Fertility preservation techniques: laboratory and clinical progress and current issues
Authors: Anderson R A
Published: December 2008

Human fertility is dependent on maturation of germ cells through meiosis and their association with supporting cells, which in the female are also the source of sex steroids. These processes are sensitive to both chemotherapy and radiotherapy thus can be damaged by anti-cancer treatments. The uterus is also sensitive to radiotherapy. Our understanding of and the ability to manipulate fertility has increased together with survival rates from many cancers, particularly those affecting children, younger men, and women. The growth of interest in fertility preservation for cancer patients is a natural union of these two fields. Sperm banking has been available for many years, and is a recognized and evidence-based option for men that should be available to all. Options for women and pre-pubertal boys and girls are, however, more experimental, other than for women of committing oocytes to fertilization and cryopreservation as embryos. This Focus Issue of Reproduction aims to address the current status of some of the clinical and laboratory aspects of this burgeoning subspecialty to highlight not only areas of progress but also areas of uncertainty where future developments are required to allow the provision of accurate information, and safe and effective treatments.
Laparoscopic or open appendectomy?
Authors: Dede Kristóf , Mersich Tamás , Zaránd Attila , Besznyák István , Baranyai Zsolt , Atkári Bence , Jakab Ferenc
Published: December 2008

A laparoszkópos appendectomia az elsőként kidolgozott minimálisan invazív sebészeti eljárások egyike, mégis a mai napig ellentmondásos a megítélése mind az előnyeit, mind az indikációit tekintve.Módszer:A szerzők áttekintik és elemzik 3 év alatt laparoszkópos (LA) és nyílt technikával appendectomizált (OA) betegeik adatait.Betegek:Az Uzsoki Utcai Kórház Sebészeti Osztályán 2005. január 1.–2007. december 31. között 273 betegnél történt appendicitis acuta diagnózissal appendectomia. Száznyolcvanöt (68%) betegnél laparoszkóposan, 88 (32%) betegnél nyílt technikával végeztük a műtétet. Két év óta alapelvünk, hogy appendicitis esetén laparoszkópos appendectomia az elsőként választandó eljárás, a legutóbbi évben az esetek 89%-ában már laparoszkóposan történt a műtét.Eredmények:Laparoszkópos kezdést követően konverziót végeztünk a betegek 27%-ánál, 35 esetben (70%) a betegség előrehaladott volta, 15 esetben (30%) technikai ok miatt. Sebfertőzés a laparoszkópos csoportban 8%-ban, a nyílt csoportban 18%-ban fordult elő (p= 0,022). A laparoszkópos és a nyílt csoport között nem volt szignifikáns különbség sem a reoperációk, sem a kórházi visszavételek tekintetében. Csonkinsufficientiát a laparoszkópos csoportban 1 esetben észleltünk, ez drén mellett spontán gyógyult. Az átlagos ápolási nap szignifikánsan csökkent a laparoszkópos csoportban (p= 0,031).Megbeszélés:A vizsgálat igazolta a laparoszkópos appendectomia előnyeit a nyílt műtéttel összehasonlítva. Gyakorlatunkban akut appendicitis gyanúja esetén elsőként választandó eljárás a laparoszkópos műtét.
Analysis of associations between mortality and biological and social-economic individual determinants
Authors: Bakacs Márta , Vitrai József , Várhalmi Zoltán , Kaposvári Csilla , Hermann Dóra , Kabos Sándor , Löv András
Published: December 2008

Az informált döntéshozatal nemzetközileg egyre elfogadottabb eszköze az egészség-hatáselemzés. A szerzők olyan statisztikai modellek kidolgozásában vettek részt, amelyek segítséget nyújtanak az egészségügyi szektoron belüli és kívüli döntések egészségre kifejtett hatásainak becsléséhez. Logisztikus regresszióval vizsgálták a mortalitást befolyásoló egyéni tényezők közül a nem, az életkor, az iskolázottság és a gazdasági aktivitás halandóságot befolyásoló szerepét az összhalandóságra, a keringési rendszer betegségei és a rosszindulatú daganatok miatti halandóságra. Az eredmények igazolták, hogy az életkorral emelkedő halandóságra a nem, az iskolázottság és a gazdasági aktivitás egyidejűleg úgy hatott, hogy egymás hatását is módosították, közöttük többszörös interakciók voltak. A halandóságot több tényező összetett hatásrendszere befolyásolja, ezért ennek vizsgálatára csakis többváltozós statisztikai módszerek alkalmasak. A közleményben bemutatott modellek kiindulópontjai lehetnek azoknak a kutatásoknak, amelyek az egyéni tényezők mellett térségi társadalmi-gazdasági tényezőket is bevonhatnak az egészség-hatáselemzésekbe.
Administração pública e gestão social: a produção científica brasileira entre 2000 e 2005
Authors: Hocayen-da-Silva Antônio João , Rossoni Luciano , Ferreira Júnior Israel
Published: December 2008

Nos últimos anos, observa-se grande esforço dos pesquisadores em fazer um balanço crítico das publicações científicas em diversas disciplinas. Porém, algumas áreas foram pouco contempladas, como a administração pública e gestão social. Buscando preencher essa lacuna, este artigo apresenta um quadro geral da produção científica em administração pública e gestão social com base nos dados levantados em 549 artigos publicados nos anais do Enanpad, entre os anos de 2000 e 2005. As variáveis analisadas em cada artigo foram: número de autores por artigo; instituição e estado de origem dos autores; proporção de trabalhos teóricos e empíricos; e método e estratégia de pesquisa. Verificou-se que a média de autores por artigo vem crescendo. A maioria enquadrou-se como teórico-empírico (76,1%). Dos artigos teórico-empíricos, aproximadamente 67% utilizaram o método qualitativo, com predomínio do estudo de caso (55,7%) como estratégia de pesquisa; porém o uso do método quantitativo vem aumentando. Entre as instituições de origem dos autores, cinco se destacaram como as mais prolíficas, respondendo por aproximadamente 50% dos artigos publicados no período; e cerca de 56% dos artigos concentraram-se em três estados do país.
Reconstrução teórica do cuidado para as práticas de saúde: um olhar a partir da produção de alunos de curso de especialização a distância
Authors: Ferreira Maria de Lourdes da Silva Marques , Cotta Rosângela Minardi Mitre , Oliveira Marilda Siriani de
Published: December 2008

Este estudo analisa a produção coletiva realizada por um grupo de tutores do curso de especialização a distância "Ativação de processos de mudança na formação superior de profissionais de saúde", sobre cuidado em saúde. A questão debatida foi: como os diferentes sentidos do cuidado devem orientar as práticas do cuidado à saúde num contexto de articulação ensino-serviço-comunidade? Utilizou-se para análise da produção a técnica de análise de conteúdo. As categorias sobre cuidado em saúde foram: ontológica, crítica, reconstrutiva e genealógica. O enfoque central foi uma abordagem do cuidado que extrapola o ato técnico, por meio de pactos, compartilhamento de poderes, parcerias e utilização do método da roda. A formação dos ativadores objetivou contribuir para uma assistência qualificada e comprometida com as necessidades dos usuários. Destaca-se a importância da articulação da academia, enquanto órgão formador, do serviço, como exercício da prática e da comunidade que receberá o cuidado, sob uma nova ótica - centrada no usuário, ou seja, enquanto sujeito participativo e protagonista do processo de produção do cuidado.
Scapular fracture: lower severity and mortality
Authors: Salimi Javad , Khaji Ali , Karbakhsh Mojgan , Saadat Soheil , Eftekhar Behzad
Published: December 2008

CONTEXT AND OBJECTIVE: The presence of scapular fracture is believed to be associated with high rates of other injuries and accompanying morbidities. The aim was to study injury patterns and their overall outcomes in patients with scapula fractures. DESIGN AND SETTING: Cross-sectional study of trauma patients treated at six general hospitals in Tehran. METHODS: One-year trauma records were obtained from six general hospitals Among these, forty-one had sustained a scapular fracture and were included in this study. RESULTS: Scapular fracture occurred predominantly among 20 to 50-year-old patients (78%). Road traffic accidents (RTAs) were the main cause of injury (73.2%; 30/41). Pedestrians accounted for 46.7% (14/30) of the injuries due to RTAs. Falls were the next most common cause, accounting for seven cases (17.1%). Body fractures were the most common type of scapular fractures (80%). Eighteen patients (43.9%) had isolated scapular fractures. Limb fracture was the most common associated injury, detected in 18 cases (43.9%). Three patients (7.3%) had severe injuries (injury severity score, ISS > 16) which resulted in one death (2.4%). The majority of the patients were treated conservatively (87.8%). CONCLUSIONS: Patients with scapula fractures have more severe underlying chest injuries and clavicle fractures. However, this did not correlate with higher rates of injury severity score, intensive care unit admission or mortality.
THE VASCULAR STRUCTURE OF THE EXTRAPLACENTAL UTERINE MUCOSA OF THE RABBIT
Authors: PARRY HELEN J.
Published: December 2008

The finer vascular system of the extra-placental uterine mucosa of the rabbit during oestrus and the early stages of pregnancy and pseudopregnancy was studied by means of the benzidine-nitroprusside blood stain and by injection.

In the oestrous uterus there is a marked mesometrial hyperaemia which intensifies during the early stages of pregnancy and pseudopregnancy.

No spiral arteries nor arterio-venous anastomoses were found in the uterine endometrium.

During the early stages of pregnancy, as the uterine mucosa proliferates, there is an intense growth of new blood vessels, accompanied by a corresponding increase in the amount of blood in the vessels. This occurs throughout the uterus at first, but after 8 days post coitum the increase continues around the conceptus but slows down and finally stops between the conceptuses and in the pseudopregnant horn.

When the trophoblast of the blastocyst wall fuses with the uterine epithelium the fusion areas become well vascularized. It is suggested that this vascularization is stimulated by the invading trophoblast.

The trophoblast actually breaks down the walls of the maternal capillaries and allows the maternal blood to bathe the embryonic syncytium and during the time that this is happening there is a marked leucocytosis around the fusion areas.

The results are discussed in relation to the previous literature and to their possible physiological significance.
THE EFFECT OF DESTRUCTION OF THE GERMINAL EPITHELIUM ON THE NUMBERS OF OOCYTES
Authors: MANDL ANITA M. , ZUCKERMAN S.
Published: December 2008

The germinal epithelium was eliminated in fifty post-pubertal albino rats by painting the ovarian surface with 10% tannic acid. Seven rats were treated bilaterally and forty-three unilaterally. The animals were killed at intervals ranging from a few hours to 469 days after the operation. Some germinal epithelium, usually abnormal in appearance, was present in eighteen out of the forty-three ovaries of the rats treated unilaterally, and in eight of fourteen ovaries of the animals dealt with bilaterally. The ovaries in the unilateral series were considerably reduced in volume. There was less involution in the bilaterally treated animals.

Normal and atretic follicles in all stages of development were present up to 469 days after the elimination of the germinal epithelium.

The total number of oocytes in the experimental animals was only slightly lower than normal, there being no significant difference (P > 0·4) between the numbers of oocytes in the experimental ovaries and in their controls. There were more normal large follicles in the control ovaries.

The relevance of these findings to the question of post-pubertal oogenesis is discussed.
NUMBERS OF NORMAL AND ATRETIC OOCYTES IN UNILATERALLY SPAYED RATS
Authors: MANDL ANITA M. , ZUCKERMAN S.
Published: December 2008

A quantitative study of the number of oocytes at different stages of development in the remaining ovary of unilaterally spayed rats has confirmed earlier results reported by Arai [1920a]. The ovary doubles in weight, and produces as many mature Graafian follicles as are found in the two ovaries of litter-mate controls. The number of primordial oocytes remains at the level normal for one ovary.
THE ACTION OF SODIUM OESTRONE SULPHATE ON THE UTERUS OF THE MOUSE IN VITRO
Authors: ROBSON J. M. , SHARAF A. A.
Published: December 2008

The effects of sodium oestrone sulphate on the uterus of the mouse in vitro have been investigated.

Motor effects are produced on the uterus of (1) oestrous animals and (2) ovariectomized animals treated with oestradiol and certain other steroids. Inhibitory effects are produced on the uterus of (1) metoestrous animals, (2) pregnant animals and (3) ovariectomized animals treated with progesterone, testosterone and certain other steroids. The antagonism between oestradiol on the one hand, and progesterone and testosterone on the other, has been studied.

Steroids which produce a condition of the uterus in which it is inhibited by sodium oestrone sulphate also inhibit the vaginal response to oestrogen in ovariectomized mice.
THE INFLUENCE OF SEX ON THE MATURATION OF THE CENTRAL NERVOUS SYSTEM IN THE ALBINO RAT
Authors: EAYRS J. T.
Published: December 2008

The growth of the body and central nervous system and the emergence of stereotyped behaviour have been studied in male and female rats during the first 24 days of life. The effects of daily injections of equine gonadotrophin on these measures have also been investigated.

The weight of the body and of the central nervous system was significantly less in the female than in the male. The daily administration of 10 i.u. of equine gonadotrophin was without effect on either.

The movements of the trunk and limbs concerned in the body-righting reflex became coordinated more slowly in the gonadotrophin-injected animals than in their litter-mate controls.

At 15 days old, male rats were able to right in mid-air more successfully than litter-mate females.

The placing reflex appeared earlier in the male than in the female. Its appearance was accelerated in the females given gonadotrophin, but not in the males.

In the ventral funiculus of the spinal cord of 24-day-old experimental animals, the axis cylinders occupied more space relative to that occupied by myelin than did those of the controls. The total amount of myelin present was unchanged. There was no sex difference in the progress of myelination in the spinal cord.

The significance of these findings in relation to the secretion of sex hormones is discussed. It is suggested that the secretion of androgen may be responsible for an acceleration of nervous maturation.
OVARIAN HYPERTROPHY AFTER UNILATERAL HYSTERECTOMY
Authors: MANDL ANITA M. , ZUCKERMAN S.
Published: December 2008

After unilateral hysterectomy the ovary on the same side undergoes temporary hypertrophy. The opposite ovary hypertrophies to a lesser extent. The greater increase in size of the ovary on the one side appears to be associated with the occurrence of oestrus. After approximately 1 week it involutes to about the size of its fellow.
THE REACTION OF THE OVARIES AND ADRENAL GLANDS OF FEMALE RATS TO OVARIAN AND MUSCLE HOMOGRAFTS
Authors: MANDL ANITA M. , ZUCKERMAN S.
Published: December 2008

The ovaries and adrenal glands of an adult rat hypertrophy after either ovarian or muscle tissue is homografted into the animal. The ovarian weight/body weight and adrenal weight/body weight ratios become significantly higher than those of normal adult female rats derived from the same colony. Anaesthesia also appears to lead to a transitory increase in the weight of the adrenals.

The possibility that the ovaries respond to certain non-specific conditions, in the same general way as do the adrenal glands, is discussed.
THE FLUORIMETRIC DETERMINATION OF OESTROGENS
Authors: BRAUNSBERG HANNELORE
Published: December 2008

Five fluorimetric methods for the determination of oestrogens have been investigated and compared. The absorption spectra of the fluorescent compounds obtained in three have been studied, and the effect of water, toluene and alcohol have been investigated.

The best method for high sensitivity is that of Bates & Cohen [1950a]; that of Finkelstein, Hestrin & Koch [1947], however, may be less influenced by any impurities present.

Toluene, water and alcohol have a marked influence on the fluorescence.

A mercury lamp may not be the most suitable source of light.

A primary filter of maximum transmission at 450 mμ will give best sensitivity.
THE EFFECT OF HIGH DOSES OF ASCORBIC ACID ON THE FUNCTIONS OF THE ADRENAL GLANDS
Authors: KAYAHAN S.
Published: December 2008

Four grams ascorbic acid given daily by mouth for 4 days increase the urinary excretion of 11-oxysteroids and decrease the excretion of 17-ketosteroids. Ascorbic acid probably acts directly on the adrenal cortex.
THE EFFECT OF HYPOTHYROIDISM ON THE GUINEA-PIG
Authors: HUMPHREYS ELIZABETH M.
Published: December 2008

Thiouracil was administered to young guinea-pigs from a month before birth until either the time of birth or until they were 8 weeks old. The basal metabolic rate of these animals was depressed, their thyroids were hyperplastic and took up tracer doses of 131I more slowly than normal. Nevertheless the growth rate of such animals did not differ significantly from that of normal control guinea pigs.
THE INFLUENCE OF OESTRONE ON THE DIVISION OF CELLS
Authors: CARTER SHEILA B.
Published: December 2008

The number of mitoses per unit area, or length of tissue, has been estimated in the epidermis of the ear, and in the epithelial linings of the oesophagus, duodenum and urethra. Specimens were taken from female rats in pro-oestrus, oestrus and the 1st and 2nd days of dioestrus, and from spayed rats which had received either no treatment or up to five injections of 25 μg of oestrone.

The results of these experiments do not confirm claims, made for various mouse tissues, that the rate of mitosis varies periodically in phase with the oestrous cycle, or that it is increased by oestrogen.
SPECIES DIFFERENCES IN THE DEOXYRIBONUCLEIC AND RIBONUCLEIC ACID CONTENTS OF LIVERS OF NON-PREGNANT AND PREGNANT MICE, GUINEA-PIGS AND CATS
Authors: CAMPBELL ROSA M. , KOSTERLITZ H. W.
Published: December 2008

1. The protein content of liver cells is almost independent of the size of the animal (mice, cats and previous results on rats, Campbell & Kosterlitz [1949]), and varies with the amount of protein eaten.

2. As has already been shown for rats, the ribonucleic acid ('RNA') content of the liver cells of non-pregnant mice, guinea-pigs and cats varies directly with the protein content of the cells. For a given protein content the mouse and rat have more RNA than the guinea-pig and cat.

3. During pregnancy there is a rise of the deoxyribonucleic acid ('DNA') content of the livers and in the protein content of the liver cells of mice (and rats), but not of guinea-pigs.

4. An excess of RNA over that predicted from the protein content of the liver cell has previously been found for the rat during pregnancy, and ascribed to the action of a placental factor on the maternal liver. A similar excess of RNA has now been observed in the mouse and, to a less extent, in the guinea-pig. It appears to be absent in the cat.

5. Possible causes of some of these species differences are considered.
THE ROLE OF HORMONAL AND DIETARY FACTORS IN THE FORMATION OF EXCESS RIBONUCLEIC ACID IN THE LIVERS OF PREGNANT RATS
Authors: CAMPBELL ROSA M. , INNES I. R. , KOSTERLITZ H. W.
Published: December 2008

1. Excess ribonucleic acid ('RNA') is defined as the difference between the RNA contents of livers of pregnant and non-pregnant rats. Large amounts of excess RNA are formed in the liver of the rat during the last week of pregnancy. Excess RNA is formed in the liver after removal, on the 14th or 15th day of pregnancy, of the foetuses, or foetuses and ovaries, or foetuses and adrenals, or foetuses, ovaries and adrenals, or pituitary, or pituitary and foetuses, or pituitary, foetuses and ovaries. Viable placentae must be present.

2. Two fractions of RNA appear to be present in the liver cells of pregnant rats. One fraction varies linearly with the protein content of the liver cells, as does the RNA of non-pregnant rats' livers. The second fraction (excess RNA) is quite independent of the protein content of the liver cells but varies linearly with the weight of the placentae and the energy, but not the protein, content of the diet.

3. Hypophysectomy lowers the amount of excess RNA by 20–25 %. After removal of the foetuses on the 14th day, the placentae do not attain the normal weight, and the amount of excess RNA is smaller than in normal pregnancy. After removal of foetuses and ovaries the placentae are larger and heavier than after removal of the foetuses alone.

4. Both adrenalectomy and ovariectomy in non-pregnant female rats cause a small rise of liver deoxyribonucleic acid ('DNA') and RNA. After hypophysectomy, there is a loss in liver RNA greater than that expected from the simultaneous loss of liver protein. The loss of RNA occurs even when the loss of liver protein is prevented by feeding the rats by stomach tube. DNA is not lost from the liver a fortnight after hypophysectomy, as long as the energy intake is normal.

5. In non-pregnant female rats oestradiol, but not progesterone, causes an increase of liver DNA and RNA. This is not found in hypophysectomized rats. Injection of an alkaline placental extract causes a significant rise of liver RNA which, however, is very much smaller than that found in pregnancy.

6. Since hypophysectomy lowers, but does not abolish excess liver RNA in pregnant rats, it is concluded that at least two factors play a role: first and foremost, an unknown factor secreted by the placenta, acting independently of the pituitary, and second, increased amounts of oestrogen apparently requiring the presence of the pituitary.
THE EFFECT OF DIFFERENT PROTEIN SOLVENTS ON THE DOSE-RESPONSE LINE FOR THE INTRAVAGINAL ADMINISTRATION OF OESTRONE IN MICE
Authors: BIGGERS J. D.
Published: December 2008

1. The proteins: egg albumin and bovine plasma albumin exert a significant influence on the action of oestrone upon the vagina, but they differ in the concentrations required to produce an effect. Egg albumin does so only in 1·0 % solutions, while plasma albumin is effective in 0·01 % solutions.

2. β-Lactoglobulin may have an effect similar to that of egg albumin.

3. Globulins, fibrinogen, and pepsin have no influence on the action of oestrone upon the vagina.

4. While 1% egg albumin causes a significant alteration only in the position of the dose-response line, 0·01% plasma albumin, in addition, depresses the slope.

5. The significance of these results in relation to (a) the intravaginal dose-response line, and (b) the physical interaction of proteins and oestrogens is discussed.
MEASUREMENT OF THE TOTAL AREA OF SECRETORY EPITHELIUM IN THE LACTATING MAMMARY GLAND OF THE GOAT
Authors: RICHARDSON K. C.
Published: December 2008

A method previously described for estimating the total surface area of secretory epithelium in the half-udder (single gland) of the goat, has been re-investigated and simplified. Fifty or more fields of lobule-alveolar tissue, at a constant magnification, are projected from histological sections taken from small blocks of fixed material selected at random, against a single line representing a diameter of the field. Twice the average number of intersections which the line makes with the epithelium lining the alveoli and intra-lobular ducts, multiplied by the volume of the half-udder, and divided by the length of the line corrected for magnification, gives an estimate of the total surface area of secretory epithelium. A highly significant correlation is obtained between the surface area and average weekly milk yields in a series of glands from ovariectomized goats brought into lactation by treatment with oestrogen alone, or in combination with progesterone, or from normal goats in lactation after kidding. An overall deficiency in surface area of epithelium is typical of the glands brought into lactation artificially by the administration of sex hormones. The ratio obtained by omitting the volume of the total gland from the formula provides a useful index of alveolar size, which is commonly much larger in glands developed in response to the injection of these hormones.
ADRENOCORTICOTROPHIN IN RELATION TO THE DIABETOGENIC ACTIVITY OF GROWTH HORMONE PREPARATIONS
Authors: REID E.
Published: December 2008

The diabetogenic activity of preparations of growth hormone (GH) in intact cats was enhanced by the additional administration of preparations of adrenocorticotrophin (ACTH). High doses of ACTH alone were not diabetogenic under these conditions.

The enhancing action of ACTH occasionally persisted for some time after cessation of ACTH injections, and was not associated with any marked lowering of the renal threshold for glucose.

With a given ACTH preparation, the diabetogenic activity of purified GH was usually enhanced less than that of crude preparations.

With a given GH preparation, the degree of enhancement differed with different ACTH preparations, and bore little relation to their effectiveness in the Sayers test. Experiments are in progress to test the possibility that these differences might merely reflect differences in the rate of absorption from the injection site.
THE EFFECTS OF HIGHLY PURIFIED POSTERIOR PITUITARY PRINCIPLES ON THE LACTATING MAMMARY GLAND OF THE RABBIT
Authors: CROSS B. A. , VAN DYKE H. B.
Published: December 2008

1. The milk-ejection activity of highly purified oxytocic and vasopressor-antidiuretic (ADH) polypeptides was determined on the intact mammary gland of the lactating rabbit.

2. When assayed in this way, 100 units of vasopressin-ADH had an activity represented by 17 units of oxytocin.

3. The lactating rabbit mammary gland is more sensitive to oxytocin than the rat uterus, and appears to be the best means at present available for assessing milk-ejection activity.
THE PETTENKOFER REACTION AS AN INDICATION OF ADRENOCORTICAL ACTIVITY
Authors: PRUNTY F. T. G.
Published: December 2008

The quantity of dehydroepiandrosterone in urine extracts has been measured by the Pettenkofer reaction. The proportion of this substance, relative to 17-ketosteroids, measured in ketonic fractions, rose significantly after gonadectomy in a testicular pseudohermaphrodite. The amount obtained from a case of post-pubertal virilism due to adrenal hyperplasia was significantly reduced by cortisone treatment. Large proportions were found in a case of adult cryptorchidism, and the total amount present increased after ACTH injection. In six of seven other patients receiving ACTH the amount of dehydroepiandrosterone increased. It is concluded that dehydroepiandrosterone is indicative of the adrenocortical contribution to 17-ketosteroid excretion in human subjects.
THE FLUORESCENCE AND ABSORPTION SPECTRA OF OESTRONE, OESTRADIOL-17β, AND OESTRIOL COMPOUNDS
Authors: AITKEN E. H. , PREEDY J. R. K.
Published: December 2008

1. Fluorescence and absorption spectra are given for oestrone, oestradiol-17β, and oestriol compounds, in response to exciting light of five different wavelengths.

2. An estimate has been made of the 'fluorescence efficiency' of each exciting wavelength.

3. On the basis of the above data, recommendations for sources of light and filters for the routine fluorimetric estimation of oestrogens are put forward.
THE FUNCTION OF ADRENALINE IN THE PRODUCTION OF PITUITARY ADRENOCORTICOTROPHIC ACTIVITY
Authors: HODGES J. R.
Published: December 2008

1. Subcutaneous injections of l-adrenaline caused adrenal ascorbic acid depletion in normal rats.

2. Previous treatment of rats with deoxycorticosterone acetate ('DCA') prevented the fall in adrenal ascorbic acid concentration caused by the administration of adrenaline. A quantitative relationship existed between the dose of adrenaline injected and the dose of DCA required to prevent its effect.

3. The application of stress stimuli resulted in a rapid fall in the ascorbic acid concentration in the demedullated adrenal glands of rats. Maximal effects were obtained as soon after the performance of the operations as in rats with normal adrenal glands.

4. Pre-treatment of adrenal-demedullated rats with DCA diminished the fall in adrenal ascorbic acid concentration caused by stress. The doses of DCA required to prevent completely the adrenal ascorbic acid depletion due to stress were of the same order as those required to produce the same effect in normal animals.

5. The possible significance of these findings is discussed.
THE ASSAY OF CORTICAL STEROIDS BY THE MOUSE EOSINOPHIL TEST
Authors: BIBILE S. W.
Published: December 2008

1. A procedure for carrying out biological assays of adrenal cortical hormone by the mouse eosinophil method is described.

2. The test is sensitive to 1 μg of cortisone; there is a linear relationship between log dose and response with a stable variance; the slope and sensitivity of the test do not change significantly throughout the year. The test is, however, inaccurate (λ=0·56) in that a fourfold increase in dose is required for the mean responses of two groups of ten mice to differ significantly.

3. Five other biologically active steroids and two of their acetates have been compared. The 11-deoxysteroids were found to be inactive. The order of potencies were: cortisone (100), hydrocortisone (78), corticosterone (37), 11-dehydrocorticosterone (24).

4. There is no significant departure from parallelism between the curves for cortisone and cortical extract (Eucortone).

5. The test is not specific for adrenal steroids, as dog plasma protein gives a similar effect in adrenalectomized mice. Therefore, biological fluids containing protein must first be extracted with organic solvents before being tested for cortical hormone activity by this method.

6. No hormone was detected in the cells of adrenal venous blood. The hormone appeared to be in the plasma.

7. Hydrocortisone in small concentrations has no direct cytolytic action on eosinophils in vitro.
THE IN VITRO ACTION OF ACTH ON THE OXYGEN CONSUMPTION OF SLICES OF CATTLE ADRENAL CORTEX
Authors: REISS M. , BRUMMEL EVA , HALKERSTON I. D. K. , BADRICK F. E. , FENWICK M.
Published: December 2008

A technique for measuring the action of small doses of ACTH on the oxygen consumption of slices of cattle adrenal cortex is described.

The oxygen consumption rate of such slices in vitro is increased by ACTH.

A linear relationship between logarithm of the dose of ACTH and the percentage increase in the rate of oxygen uptake is obtained with this method, and its suitability for biological assay purposes has been investigated.

The question of the specificity of this action of ACTH is discussed.
A CHROMATOGRAPHIC INVESTIGATION OF Δ4-3-KETOSTEROIDS AND α-KETOLIC STEROIDS IN HUMAN URINE
Authors: de COURCY CONSTANCE , BUSH I. E. , GRAY C. H. , LUNNON J. BARBARA
Published: December 2008

The Δ4-3-ketosteroids and α-ketolic steroids present in extracts prepared by five different procedures from urine have been examined by paper chromatography.

The first extract, which consisted of those steroids extractable with chloroform at neutral pH contained cortisone and cortisol* and one to four unknown Δ4-3-ketosteroids. The second extract, representing steroids extractable immediately after acidification to pH 1 contained very little additional material. The third fraction consisted of extra steroids liberated after standing for 24 hr with acid; this rarely contained any detectable steroid material. A fraction which contained chloroform-soluble conjugated steroids was found to include small quantities of cortisone and cortisol and the other Δ4-3-ketosteroids. The final fraction contained large quantities of steroids liberated by hydrolysis with β-glucuronidase; these were mainly α-ketolic steroids including pregnane-3α: 17α: 21-triol-11: 20-dione, together with other unknown Δ4-3-ketosteroids.

The distribution of the steroids in the various fractions is discussed and suggestions are made concerning the possible structure of some of the unknown steroids.
PRECOCIOUS PUBERTY AND CHORIOEPITHELIOMA OF THE PINEAL GLAND WITH REPORT OF A CASE
Authors: ZONDEK H. , KAATZ A. , UNGER H.
Published: December 2008

The case of a 6 year-old boy with precocious puberty suffering from recurrent cerebral accidents suggestive of subarachnoid haemorrhages is reported. At operation a haemorrhagic tumour involving the region of the pineal gland was discovered. Histological examination showed the tumour to be a chorioepithelioma. The question as to whether precocious sexual development was the result of an inherent endocrine activity of the tumour cells or of mechanical involvement of the neighbouring diencephalic centres, is discussed.
A QUANTITATIVE ANALYSIS OF THE ROLE OF OESTROGEN IN MAMMARY DEVELOPMENT IN THE RAT
Authors: SILVER MARIAN
Published: December 2008

A quantitative analysis of mammary development in the gonadectomized Hooded Norway rat treated with various levels of oestradiol dipropionate (Oe. DP.) from the 20th to 80th day of life was carried out. The relative rate of mammary growth in the oestrogen-treated animals was compared with that found in intact and gonadectomized control rats. Over the dose range 0·05–1·0 μg Oe. DP./2 days a positively allometric mammary-growth phase was induced, but the equilibrium constants obtained for all groups, except the males receiving 1·0 μg Oe. DP., were significantly lower than the value of 3·40±0·17 for the intact female. In the majority of oestrogen-treated groups no statistically significant differences between the values of α were found, although the approximate time of onset of the artificially-induced allometric phase of growth appeared to be related to the dose of hormone given. When a dose of Oe. DP. increasing proportionately with the body weight was employed, the resultant rate of mammary growth relative to body growth (α=3·70±0·13) was similar to that found in the intact female.

An analysis of the number of ducts and side-buds present in the thoracic glands after various treatments at the end of the 60-day experimental period was made in the female groups. While duct development at all levels of oestrogen treatment was similar to that found in the intact female, the degree of side-bud proliferation appeared to be dependent on the dose of Oe. DP. administered.