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PubMed1997

Suicide by age, ethnic group, coroners' verdicts and country of birth. A three-year survey in inner London.

BACKGROUND: Information on suicide in ethnic and immigrant groups in England and Wales is limited. METHOD: A three-year (1991-1993) survey was conducted of all unnatural deaths of residents of an urban area. 'True likely' and 'official' age-adjusted suicide rates were compared by ethnicity and, for Whites, birthplace. RESULTS: Irrespective of verdict, 329 likely suicides were identified. Relatively few ethnic minority and White immigrant suicides had received a suicide verdict. Afro-Caribbeans had relatively low, and young Indian women relatively high suicide rates. Rates of Scottish- and Irish-born residents were 2.1 to 2.9 times higher than the local base rate. Young White males' rates were higher than those of the elderly. CONCLUSIONS: Classification of suicide is biased with respect to ethnicity and national origin. Rate patterns for ethnic minority groups reflect patterns seen in attempted suicide. In this deprived area, young White male suicide rates have surpassed those among the old.

Adult↗
PubMed1975

Progestational function of perifused rat corpora lutea.

Corpora lutea (CL) from synchronously ovulated, prepubertal rats remained viable in perifusing Eagle medium (Dulbecco modified) flowing at a rate of 1 ml/hr. As an index of viability, progesterone (P) and 20alpha-hydroxypreng-4-ene-3-one (20alpha-OH-P) were determined by radioimmunoa-say in effluent media. Corpora lutea removed on the 2nd day of diestrus (D-2) or the 2nd day of pseudopregnancy (PP-2) showed fatigue by a continuous decline in the concentrations of effluent progestins. P decreased from 2 to 0.2 ng/ml/CL during an interval of 5 hr, while 20alpha-OH-P decreased from 2.2 to about 0.7 ng/ml/CL. In contrast corpora lutea taken on PP-4 maintained higher progestin levels in the effluent media. P present initially at 2.2 ng/ml/CL decreased to 0.73 ng/ml/CL; 20alpha-OH-P, initial concentration 0.84 ng/ml/CL, decreased to 0.41 ng/ml/CL. The greater functionality of PP-4 CL indicated by the continued predominance of , suggested an in vivo imposition of a luteotropic stimulus occurring after PP-2. Addition of bovine LH (NIH-LH-B8, 20 mug/ml) to the perifusing medium stimulated steroidogenesis by PP-2 CL during which 20alpha-OH-P levels remained between 2.3 and 3.2 ng/ml/CL throughout perifusion, while P secretion decreased from 2.9 to 0.9 ng/ml/CL. Prolactin (NIH-P-B3, 20 mug/ml), did not significantly alter the original secretion pattern of PP-2 CL. During combined prolactin (20 mug/ml) and LH (2 to 10 mug/ml) perifusion, P secretion predominated, decreasing from 3.9 to 1.0 ng/ml/CL; 20alpha-OH-P decreased from 1.2 to 0.7 ng/ml/CL.

Animals↗
PubMed1976

Control of prolactin and growth hormone secretion in mice by obesity.

Prolactin (PRL) and growth hormone (GH) secretions in mice rendered obese by the administration of gold thioglucose (GTG) are abnormal. The objective of the present experiments was to determine whether the effects were related to the drug or to the resultant obesity. Perphenazine-induced PRL release in normal mice and in GTG-injected non-obese mice was compared to that of GTG-injected obese mice after the initial development of obesity, after body weight reduction by diet control and after the resumption of obesity by ad lib. feeding. The GTG-injected mice which did not become obese had greater (50%) than normal levels of serum PRL following perphenazine stimulation in 2 of 3 experiments. This suggested that the injection of GTG directly affected the control mechanism for PRL secretion, but that the abnormal PRL secretion was probably not the cause of obesity that develops after GTG treatment. Perphenazine-induced PRL levels in mice rendered obese with GTG were much greater (2-3 times higher than normal). However, the unusually high levels of PRL were totally abolished when the body weights of these mice were brought down to normal by dietary restriction. Conversely, when obesity was permitted to recur by giving the mice free access to food, PRL levels reverted back to the original obese pattern. The concentrations of GH were usually lower than normal in GTG-obese mice, and these levels were also more often associated with the development of obesity than with the injection of GTG. The data show a marked influence of obesity on the control of PRL and GH secretions in the mouse.

Animals↗
PubMed2003

Jawsfest: new perspectives on neural crest lineages and morphogenesis.

The neural crest is a fascinating population of cells that migrate long distances in the developing embryo to generate many different derivatives. It also occupies a central position in the origin and patterning of the vertebrate head, and has generated debates about issues such as cell programming versus plasticity and the role of cell death in early morphogenesis. These aspects of the field were revisited and discussed in a recent meeting organized to honour the retirement of Jim Weston and his contribution to the field.

Animals↗
PubMed1996

Initiation patterns of flower and floral organ development in Arabidopsis thaliana.

Sector boundary analysis has been used to deduce the number and orientation of cells initiating flower and floral organ development in Arabidopsis thaliana. Sectors were produced in transgenic plants carrying the Ac transposon from maize inserted between the constitutive 35S promoter and the GUS reporter gene. Excision of the transposon results in a blue-staining sector. Plants were chosen in which an early arising sector passed from vegetative regions into the inflorescence and through a mature flower. The range of sector boundary positions seen in mature flowers indicated that flower primordia usually arise from a group of four cells on the inflorescence flank. The radial axes of the mature flower are apparently set by these cells, supporting the concept that they act as a structural template. Floral organs show two patterns of initiation, a leaf-like pattern with eight cells in a row (sepals and carpels), or a shoot-like pattern with four cells in a block (stamens). The petal initiation pattern involved too few cells to allow assignment. The numbers of initiating cells were close to those seen when organ growth commenced in each case, indicating that earlier specification of floral organ development does not occur. By examining sector boundaries in homeotic mutant flowers in which second whorl organs develop as sepal-like organs rather than petals, we have shown that their pattern of origin is position dependent rather than identity dependent.

Arabidopsis↗
PubMed1984

Local circuit interactions in synchronization of cortical neurones.

Under certain circumstances large numbers of neurones in the mammalian central nervous system (CNS) can discharge simultaneously. An example of such activity is recorded from a hippocampal slice in the presence of agents which block synaptic inhibition. This synchronized discharge occurs spontaneously in a rhythmic fashion or may be triggered by stimulation of any afferent pathway. Its generation appears to involve local circuit interactions. The favourable conditions offered by an in vitro preparation have allowed the cellular events during this activity to be examined in some detail. Three factors appear to be critically involved in the synchronization process. Firstly, the intrinsic ability of neurones to generate bursts, secondly, the existence of powerful recurrent excitatory connections, and thirdly the absence of inhibition which normally prevents the spread of bursting activity through the recurrent connections. Computer simulations show that in a sparsely connected network of bursting neurones activity initiated in a few cells may spread through recurrent connections until eventually the whole population discharges simultaneously. Rhythmic discharges similar to those described here also underly various CNS functions including centrally-originating motor patterns. It remains to be determined whether neuronal properties and connectivity found to be important in this hippocampal rhythm may also play a role in the generation of other rhythmic activities in the mammalian CNS.

Animals↗
PubMed1982

The central nervous origin of the swimming motor pattern in embryos of Xenopus laevis.

Rhythmic motor nerve activity was recorded in stage 37/38 Xenopus embryos paralysed with curare. The activity was similar to the swimming motor pattern in the following ways: cycle period (40-125 ms), alternation of activity on either side of a segment, rostro-caudal phase lag. Episodes of rhythmic motor activity could be evoked by stimuli that evoke swimming and inhibited by stimuli that normally inhibit swimming. On this basis we conclude that the swimming motor pattern is generated by a central nervous mechanism and is not dependent on sensory feedback. In addition to the swimming pattern, another pattern of motor activity ('synchrony') was sometimes recorded in curarized embryos. In this, the rhythmic bursts on either side of a segment occurred in synchrony, and the rhythm period (20-50 ms) was half that in swimming. This was probably not an artifact of curarization as there were indications of a similar pattern in uncurarized embryos. Its function remains unclear.

Animals↗
PubMed2006

Advice from a medical expert through the Internet on queries about AIDS and hepatitis: analysis of a pilot experiment.

BACKGROUND: Advice from a medical expert on concerns and queries expressed anonymously through the Internet by patients and later posted on the Web, offers a new type of patient-doctor relationship. The aim of the current study was to perform a descriptive analysis of questions about AIDS and hepatitis made to an infectious disease expert and sent through the Internet to a consumer-oriented Web site in the Spanish language. METHODS AND FINDINGS: Questions were e-mailed and the questions and answers were posted anonymously in the "expert-advice" section of a Web site focused on AIDS and hepatitis. We performed a descriptive study and a temporal analysis of the questions received in the first 12 months after the launch of the site. A total of 899 questions were received from December 2003 to November 2004, with a marked linear growth pattern. Questions originated in Spain in 68% of cases and 32% came from Latin America (the Caribbean, Central America, and South America). Eighty percent of the senders were male. Most of the questions concerned HIV infection (79%) with many fewer on hepatitis (17%). The highest numbers of questions were submitted just after the weekend (37% of questions were made on Mondays and Tuesdays). Risk factors for contracting HIV infection were the most frequent concern (69%), followed by the window period for detection (12.6%), laboratory results (5.9%), symptoms (4.7%), diagnosis (2.7%), and treatment (2.2%). CONCLUSIONS: Our results confirm a great demand for this type of "ask-the-expert" Internet service, at least for AIDS and hepatitis. Factors such as anonymity, free access, and immediate answers have been key factors in its success.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Development of chronic human chagas cardiopathy in the hinterland of the Paraíba State, Brazil, in a 4.5 year period].

Two sectional studies about chronic Chagas' disease were performed at a 4.5 year interval, involving the urban populations of Agua Branca, Catingueira, Emas, Imaculada, Mãe D'Agua, Olho D'Agua, Piancó and São José de Caiana counties in the Sertão region of the State of Paraíba. The evolution of heart disease was evaluated in 125 matched pairs of chronic chagasic and non-chagasic patients of the same sex, age and county of origin through electrocardiograms (ECG) at rest. The following evaluation criteria were considered: unchanged - no change in the original ECG pattern; progressive-changes in ECG pattern from normal to abnormal or deterioration of ECG abnormalities; and ECG normalization. In chagasic patients evolution of the disease was unchanged in 101 (80.8%), progressive in 13 (10.4%) and ECG normalization in 11 (8.8%), while those observed in non-chagasic patients were respectively values 117 (93.6%), 6 (4.8%) and 2%) patients. Findings indicate that the share of Chagas-linked etiological component affecting the development of chronic Chagas cardiopathy was 5.9% with an estimated annual average of 1.3%. There was no significant difference in the frequency of progressive disease between the sexes either in the chagasic or in the non-chagasic group. On the other hand, progression of heart disease occurred earlier among chagasic patients. Lethality caused by heart disease was 1.6% (2 cases) in the chagasic group and zero in the non-chagasic group during the period under survey. These morbidity and mortality rates were significantly lower than those found in endemic areas such as Virgem da Lapa and Pains-Iguatama in the State of Minas Gerais and can probably be attributed to the weaker pathogenic it of human infection by Trypanosoma cruzi in the Paraíba hinterland.

Adolescent↗
PubMed1982

Electron microscopic observations on single cilia in the intrahepatic biliary ducts in some birds.

The intrahepatic biliary passage in five species of birds was investigated with the transmission electron microscope. The avian liver was characterized by a frequent occurrence of intralobular bile ductules and canaliculo-ductular junctions in the parenchyma. It was further characterized by solitary bile ductular epithelial cells intercalated among hepatocytes surrounding bile canaliculi. The present study first revealed that avian bile ductular epithelial cells possess a long single cilium. Its basal body (distal centriole) was connected to a basal foot and slender rootlet and accompanied by a proximal centriole. The hepatocytes facing the bile passage possessed no cilium, although they frequently had a diplosome in their apical cytoplasm. The single cilia of the bile ductular epithelium gradually tapered toward the tip. The original fiber pattern in the most proximal part was peripheral 9 doublets +0. In the ciliary shaft, the doublets altered into singlets which were diminished in number gradually toward the distal parts of the shaft, so that in the tip only one singlet remained. Since these fiber patterns in the single cilia markedly deviated from the 9 + 2 fiber pattern of the ordinary motile cilia, they may not be motile, but properly regarded as sensory or chemoreceptors.

Animals↗
PubMed1990

The factor structure of the Menstrual Distress Questionnaire--Dutch.

The factor structure of the Dutch adaptation of the Menstrual Distress Questionnaire (MDQ) was studied in a group of 702 women with high probability of premenstrual symptoms. The original factor pattern could not be replicated. Essentially four factors were found: negative affect, concentration, pain, and water retention. This indicates the importance of psychological and somatic symptoms in the premenstrual syndrome.

Adult↗
PubMed1979

Cytochemistry of esterases.

Esterases are enzymes that cleave aliphatic and aromatic ester bonds. With the use of synthetic substrates, esterases can be demonstrated in hematopoietic cells. Using alpha naphthyl acetate or alpha naphthyl butyrate, nonspecific esterase activity can be demonstrated. Intense activity of nonspecific esterase that is inhibited by fluoride is characteristic of cells of monocytic or reticulum cell origin. Using naphthol ASD-chloroacetate, specific esterase activity can be detected. Specific esterase is a lysosomal enzyme and is a useful marker for cells of granulocytic origin. Distinctive patterns of specific and nonspecific esterase activities are found in marrow cells from patients with various types of hematologic disorders. With the use of electrophoretic techniques, isoenzymatic analysis of esterases can be achieved.

Animals↗
PubMed1976

Surgical anatomy of the proximal anterior cerebral artery.

The authors present this study of proximal anterior cerebral arteries in the normal human to provide a clearer basis for strategy in aneurysm surgery. They describe patterns of origin of branches, their subarachnoid course, and parenchymal distribution. Branches that originate from the anterior cerebral artery at the internal carotid bifurcation perfuse the genu and contiguous posterior limb of the internal capsule and the rostral thalamus. Proximal 4-mm branches supply the anterior limb of the internal capsule, the neighboring hypothalamus, anteroventral putamen, and pallidum. The remaining anterior cerebral artery proximal to the communicating artery sends branches to the optic chiasm, the adjacent hypothalamus, and the anterior commissure. Heubner's artery arises directly opposite the anterior communicating artery to supply much of the striatum and internal capsule rostral to the anterior commissure. The anterior communicating artery branches supply the fornix, corpus callosum, septal region, and anterior cingulum. The parenchymal distribution of these end arteries may be surmised from the site of origin named vessels. With this anatomical information one can avoid interruption of blood supply to vital structures when dealing with the anterior cerebral artery and its branches.

Adult↗
PubMed1990

Benign proliferative disorders of the breast.

Fibrocystic disease of the breast has been generally regarded as a disorder due to either excess hormonal stimulation or an exaggerated proliferative response by hypersensitive breast epithelium. The unique lobular lesion-adenosis- and its variants have been regarded as non-neoplastic and non-preneoplastic glandular hypertrophy and hyperplasia, and have different organoid patterns and origins. We have examined a total of 242 cases previously diagnosed as 'fibrocystic disease' at the Department of Pathology with the purpose of clarifying the variants of adenosis in detail and refining the infinitely large 'fibrocystic disease' classification as non-proliferative fibrocystic change and proliferative disorders, such as epitheliosis and atypical hyperplasia. In this study, 224 cases (92.5%) were nonproliferative disease, mostly adenosis (40.1%), and 18 cases (7.5%) were proliferative disease, which consisted of moderate to florid hyperplasia and epitheliosis.

Adult↗
PubMed1997

[Relationship between reaction of membrane potential and size of glomus cells in rat carotid body during hypoxia].

The membrane potentials (Em) of 85 cultured isolated glomus cells were measured by intracellular recording. The shapes of glomus cells were recorded by microscopic photograph and the cell diameter was measured by micrometer enlarger. The glomus cells with different diameters exhibited two distinct responses to hypoxia. The glomus cells with diameter shorter than 10 microns were depolarized in response to hypoxia, while the cells with diameter over 10 microns were hyperpolarized during hypoxia. Thus, it is sugested that glomus cells may be divided into two functionally different subtypes. Although the smaller glomus cells depolarized more seriously under extreme hypoxia, the degree of hypoxia could not change the original response pattern of glomus cells to hypoxia.

Animals↗
PubMed1999

The angular branch of the thoracodorsal artery and its blood supply to the inferior angle of the scapula: an anatomical study.

An anatomical study of the thoracodorsal arterial system was performed; it focused on the angular branch. The aim of the study was to document the anatomical variations of this pedicle and to delineate the area of supply to the inferior angle of the scapula with a view to free bone transfer. A total of 81 cadaver dissections were performed; they revealed the constant presence of the thoracodorsal artery and four vascular patterns of origin of the angular branch. Selective India ink perfusion studies performed on 11 sides in six fresh cadavers demonstrated a reliable supply to the inferior angle of the scapula to the extent of 6 cm of the vertebral margin and 3 cm of the lateral margin of the scapula. Histologic analysis of sections of this region of the scapula confirmed the presence of ink within the periosteal, cortical, and medullary vascular channels, implying the viability of this area of bone if transferred based on the angular branch.

Cadaver↗
PubMed1999

Caries experience, dental health behaviour and social status--three comparative surveys among Danish military recruits in 1972, 1982 and 1993.

OBJECTIVE: To compare caries experience among young Danish men in 1972, 1982 and 1993; and on the same occasions to describe relationship between their utilisation of regular dental care and social status, as well as the relationship between their caries experience, utilisation of dental services and social status. DESIGN: During their routine health examinations in 1972, 1982 and 1993 all recruits enlisted in the Danish Air Force were subjected to an additional oral examination combined with a structured socio-dental questionnaire. Identical methods were applied in each of the three surveys. SETTING: Dental clinics at air bases in Denmark. SUBJECTS: 4,103 male military recruits, aged 18 to 25 years. OUTCOME MEASURES: Caries was registered in accordance with the WHO Basic Methods 1971. The questionnaire provided information on age, place of residence during childhood, social origin, and patterns of utilisation of dental services. RESULTS: The findings indicated a considerable decrease in average caries experience from 16.6 DMFT in 1972 to 11.8 in 1982 and 6.2 in 1993. The results further documented markedly increased availability of public school dental health services, the coverage rising from 33% in 1972 to 65% in 1982 and 100% in 1993, as well as moderately increased utilisation of regular dental care with private practitioners, rising from 71% in 1972 to 86% in 1982 and 84% in 1993. In 1993 as in 1982 and 1972, recruits who used the public school dental health services and also received regular dental care after their school leaving age showed the lowest average caries experience. CONCLUSIONS: The findings indicate a marked decrease in average caries experience and an increased utilisation of dental services among Danish young men from 1972 to 1993. However, in 1993 the least privileged social group continued to maintain the highest average caries experience and the lowest rate of utilisation of regular dental care.

Adolescent↗
PubMedDate not supplied

[Molecular characterization of autochthonous clinical isolates of Histoplasma capsulatum var. capsulatum using RAPD-PCR].

The aim of our work was to determine the genotypic relatedness among H. capsulatum isolates from Argentinian patients with or without AIDS and isolates from other sources and geographic origins. We analyzed band patterns of 16 isolates obtained by RAPD-PCR, 11 Argentinian clinical isolates (8 from patients with AIDS and 3 from patients without AIDS), 2 strains from the CDC, 2 isolates from Mexico and one isolate from Uruguay. With the band patterns obtained, we built a dendrogram, which showed 3 major groups. Group I contained 2 isolates from Mexico, group II 1 strain from CDC and group III included 13 isolates, and was divided into 4 subgroups. Subgroup IIIa contained 2 isolates from patients with and without AIDS. Subgroup IIIb included isolates from patients without AIDS from Chaco. Subgroup IIIc contained 7 isolates from Argentina (from Buenos Aires province) and the Uruguayan isolate (6 isolates from patients with AIDS). Subgroup IIId included only one strain from CDC. All the Argentinian and the Uruguayan isolates went into group III, subgroups IIIa, IIIb and IIIc. This is a preliminary study; however, a relatedness of the RAPD-PCR band patterns and the geographic origin was observed. Although there might be a probable association between immunocompromised patients with AIDS and infective capability of some H. capsulatum isolates, further studies with a larger number of isolates from different sources and geographic origins are necessary to confirm these results.

AIDS-Related Opportunistic Infections↗