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91.
Cultivation and partial characterization of spiroplasmas in cell cultures. 总被引:1,自引:1,他引:1
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Spiroplasmas were propagated in the Drosophila melanogaster cell line Dm-1. Spiroplasma citri and unidentified strains (corn shunt organism, 277F [tick isolate], powder puff, BNR-1, honey bee, and OBMG) grew to 10(8) to 10(9) colony-forming units per ml and could be passaged. Cytopathic effect (CPE) varied with the infecting spiroplasma. The honey bee isolate killed Dm-1 within 2 to 4 days and produced CPE in four mammalian cells tested. At 25 degrees C, suckling mouse cataract agent produced no CPE in Dm-1 cells. Dm-1 cells did not support growth of the spiroplasmal sex ratio organism. Spiroplasmas could be detected in the cell cultures by agar inoculation, dark-field microscopy, scanning electron microscopy, and DNA fluorescent staining. The uridine phosphorylase test showed significant levels of conversion of [14C]uridine to [14C]uracil for all but some plant isolates: S. citri, corn shunt organism, lettuce, cactus, and powder puff strains, the first mycoplasmas to lack the enzyme. Primary isolations of corn shunt organism from infected corn plants were made in Dm-1 and I-XII cultures. The course of corn stunt organism infection of Dm-1 was monitored for three passages. The use of agarose and Dienes staining of the colonies improved growth and colony counting of corn stunt organism. The number of viable infected DM-1 cells decreased from 1.2 x 10(7) at passage 1 to 7.0 x 10(6) at passage 2 and 3 x 10(5) at passage 3. 相似文献
92.
Ph. Heitz H. Steiner F. Halter F. Egli J. P. Kapp 《Virchows Archiv : an international journal of pathology》1971,353(4):312-324
Summary Clinical, pathological and biochemical data from a twelve year old boy with hypoglycaemic attacks and hyperinsulinism are presented. A pancreatic islet cell adenoma was diagnosed by ultrasonic scanning and enucleated from the head of the pancreas. Histological study revealed a mixed cellular population consisting of A1- and B-cells. Large amounts of extravascular amyloid deposited were found between the cell strands. The tumour extract produced a prompt elevation of gastric acid secretion in the rat gastrin bio-assay. It is concluded that this islet cell tumour was a combined gastrinoma-insulinoma. The possible pathogenesis of this variety of the multiple endocrine adenoma syndrome is discussed. Monocellular-multihormonal islet cell tumours might arise from biochemically multipotent endocrine stem cells, whereas the multicellular-multihormonal type could either be a regulatory neoplasia or be derived from different neuroendocrine cells.
Zusammenfassung Bei einem übergewichtigen 12jährigen Knaben mit Hypoglykämieanfällen und erhöhtem Blutinsulinspiegel konnte durch Ultraschall ein Tumor des Pankreaskopfes dargestellt werden. Das exstirpierte Gewebe erwies sich histologisch als ein aus A1- und B-Zellen aufgebautes Inselzelladenom mit ausgedehnten extravasculären Amyloidablagerungen. Ein Extrakt aus dem Tumorgewebe bewirkte eine sofortige Zunahme der Magensäuresekretion am perfundierten Rattenmagen. Diagnose: Insulinom-Gastrinom. Monocellulärplurihormonelle Inselzelltumoren leiten sich möglicherweise von biochemisch pluripotenten Stammzellen der Langerhansschen Inseln her. Pluricellulär-plurihormonelle Adenome sind hingegen eher als Regulationsgeschwülste aufzufassen, könnten aber auch von verschiedenen neuroendokrinen Zellen abstammen.相似文献
93.
Ectodermal dysplasia with acanthosis nigricans (Lelis syndrome) 总被引:2,自引:0,他引:2
A 31-year-old male patient with ectodermal dysplasia and acanthosis nigricans is described. Clinical findings included hypotrichosis, hypohidrosis, palmoplantar hyperkeratosis, nail dystrophy, early onset loss of permanent dentition, mental retardation, and acanthosis nigricans. The findings suggest the diagnosis of Lelis syndrome, as described on the basis of seven unrelated cases. A review concerning this condition is also presented. 相似文献
94.
Steiner I 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2004,47(2):141-145
Karl Rokitansky was born on 19th February 1804 in the historic Czech town of Hradec Králové (K?niggr?tz). During 1821-1824 he studied for 3 years at the medical faculty of Prague University. In the archives of Charles University there is a record of Rokitansky's performance during these three years. At the university he met J. E. Purkyne who was teaching anatomy at that time. Relationship between the two world--renowned medical scientists of Czech origin is discussed. 相似文献
95.
96.
H. Noreen L. Steiner M. Davidson S. Johnson M. Segall A. B. Begovich 《Tissue antigens》1997,49(5):512-516
Six new DPB1 alleles were identified by PCR-SSOP methodologies in the course of a retrospective study of the role of HLA matching in the outcome of unrelated donor bone marrow transplantation. Sequencing confirmed that five of these alleles (DPB1*5901, *6801, *7101, *7201, and *7301) represent novel combinations of previously described sequence motifs in the variable regions of DPB1; the sixth (DPB1*7001) appears to result from a novel point mutation. These data support previous observations which suggest that multiple mechanisms, including segmental exchange and mutation, appear to be responsible for generating sequence diversity at the DPB1 locus. The extremely low discrepancy rate of 0.1% between the two laboratories which typed the samples, and the ability to predict the new sequences from probe hybridization patterns, indicate that SSOP is an accurate and efficient method for studying polymorphism at DPB1. 相似文献
97.
Conservative treatment of cervical pregnancy by curettage and local prostaglandin injection 总被引:2,自引:4,他引:2
Spitzer D; Steiner H; Graf A; Zajc M; Staudach A 《Human reproduction (Oxford, England)》1997,12(4):860-866
Recently, various conservative regimens for the treatment of cervical
pregnancy have been introduced to preserve fertility in young women, with
methotrexate being one of the most widely used drugs. The success of
conservative treatment depends on early preoperative diagnosis. We report
three cases of first trimester cervical pregnancy, successfully treated by
curettage to evacuate the conceptus, followed by local prostaglandin
instillation to prevent severe haemorrhage. In one patient, intra-amniotic
instillation of hyperosmolar glucose was necessary to terminate fetal
cardiac activity. beta-Human chorionic gonadotrophin returned to normal
within 3 weeks in one patient and within 7 weeks in another, both of whom
became pregnant again within 1 year, resulting in term deliveries. The
third patient was lost to follow-up after 1 week. The advantage of
prostaglandin and curettage is the absence of major side-effects to the
mother or the fetus of a subsequent pregnancy. The management strategies
used in the treatment of cervical pregnancies and the results obtained
since the introduction of methotrexate in 1989 are discussed in the context
of previously published literature. The incidence of subsequent pregnancies
among women treated medically versus women treated surgically is reported.
相似文献
98.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
99.
Gonadotrophin-releasing hormone agonist dose-dependency of pituitary desensitization during controlled ovarian hyperstimulation in IVF 总被引:2,自引:2,他引:2
Janssens RM; Vermeiden JP; Lambalk CB; Schats R; Schoemaker J 《Human reproduction (Oxford, England)》1998,13(9):2386-2391
The aim of this study was to find the minimal effective daily s.c. dose of
the gonadotrophin-releasing hormone (GnRH) agonist, triptorelin acetate,
that suppresses the GnRH-induced release of luteinizing hormone (LH) at
time of human chorionic gonadotrophin (HCG) injection and thereby prevents
spontaneous LH surges during in-vitro fertilization (IVF) stimulation
cycles. Therefore, a double-blind, prospective and randomized titration
study was performed. A total of 48 IVF patients were divided into four
groups of 12 patients. Each group received a different dose of triptorelin
acetate, namely 5, 15, 50 or 100 microg s.c. daily. Standard ovarian
stimulation was carried out using urinary follicle stimulating hormone
(FSH) preparations. A 500 microg GnRH test was performed 90 min before the
HCG injection in order to measure the degree of pituitary desensitization.
Spontaneous LH surges were not detected in any of the groups, although
three patients in the 5 microg group had ovulated at the time of ovum
retrieval. The pituitary LH response to the GnRH test at time of HCG,
expressed as area under the curve (AUC), appeared to be dose-dependent.
Thus, a daily s.c. dose of 100 microg triptorelin acetate appears to be too
high, since adequate desensitization of the pituitary (i.e. no spontaneous
LH surge) can be achieved with doses as low as 15 and 50 microg.
相似文献
100.
Bals-Pratsch M; De Geyter C; Muller T; Frieling U; Lerchl A; Pirke KM; Hanker JP; Becker-Carus C; Nieschlag E 《Human reproduction (Oxford, England)》1997,12(5):896-904
Preliminary data have suggested that female infertility due to corpus
luteum insufficiency may be caused by subclinical hypothyroidism
[exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin-
releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been
recommended to achieve pregnancies in subclinical hypothyroid women. This
controlled study was carried out in order to investigate the biochemical
diagnosis of subclinical hypothyroidism as a possible infertility factor.
Five infertile patients (aged 25-36 years) with subclinical hypothyroidism
(n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1)
and five healthy controls (aged 22-39 years) with normal thyroid function
(stimulated TSH <15 microU/ml), regular cycles and no history of
infertility were studied in the early follicular phase. In the pre-study
evaluation, eight of 23 volunteers (34.8%) had to be excluded because of
subclinical hypothyroidism with stimulated TSH values (TSHs) >15
microU/ml. Cycle function of patients and controls was compared by the
method of LH pulse pattern analysis. Therefore blood samples were drawn
every 10 min during a 24 h period. Sleep was recorded from midnight to 7
a.m. Repetition of the TRH tests at the end of the 24 h blood sampling
period confirmed the difference in stimulated TSH values of the two study
groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin
showed no differences between patients and controls for pulse frequency,
amplitude, height, length, area under curve (AUC) and the 24 h mean. Even
the hypothyroid patient had a normal LH pulse pattern. Additional
measurement of melatonin in pooled sera every 30 min gave the
well-documented diurnal profiles during day and night for both groups.
Patients had significantly higher melatonin values at seven time points
during the night. Peaks for LH, TSH, prolactin and cortisol were correlated
with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We
concluded that corpus luteum insufficiency in female infertility cannot be
explained by subclinical hypothyroidism and thus should not be treated with
L-thyroxine for fertility reasons.
相似文献