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71.
Tiffani J. Mungoven Kasia K. Marciszewski Vaughan G. Macefield Paul M. Macey Luke A. Henderson Noemi Meylakh 《The journal of headache and pain》2022,23(1)
BackgroundThe precise underlying mechanisms of migraine remain unknown. Although we have previously shown acute orofacial pain evoked changes within the brainstem of individuals with migraine, we do not know if these brainstem alterations are driven by changes in higher cortical regions. The aim of this investigation is to extend our previous investigation to determine if higher brain centers display altered activation patterns and connectivity in migraineurs during acute orofacial noxious stimuli.MethodsFunctional magnetic resonance imaging was performed in 29 healthy controls and 25 migraineurs during the interictal and immediately (within 24-h) prior to migraine phases. We assessed activation of higher cortical areas during noxious orofacial heat stimulation using a thermode device and assessed whole scan and pain-related changes in connectivity.ResultsDespite similar overall pain intensity ratings between all three groups, migraineurs in the group immediately prior to migraine displayed greater activation of the ipsilateral nucleus accumbens, the contralateral ventrolateral prefrontal cortex and two clusters in the dorsolateral prefrontal cortex (dlPFC). Reduced whole scan dlPFC [Z + 44] connectivity with cortical/subcortical and brainstem regions involved in pain modulation such as the putamen and primary motor cortex was demonstrated in migraineurs. Pain-related changes in connectivity of the dlPFC and the hypothalamus immediately prior to migraine was also found to be reduced with brainstem pain modulatory areas such as the rostral ventromedial medulla and dorsolateral pons.ConclusionsThese data reveal that the modulation of brainstem pain modulatory areas by higher cortical regions may be aberrant during pain and these alterations in this descending pain modulatory pathway manifests exclusively prior to the development of a migraine attack. 相似文献
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74.
PN McDOUGALL PM LOUGHNAN NT CAMPBELL M HOCHMANN BJ TIMMS WW BUTT 《Journal of paediatrics and child health》1995,31(4):292-296
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
75.
76.
Kroese ED; Dortant PM; van Steeg H; van Oostrom CT; van der Houven van Oordt CW; van Kranen HJ; de Vries A; Wester PW; van Kreijl CF 《Carcinogenesis》1997,18(5):975-980
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to
their low spontaneous tumour incidence and their increased sensitivity
towards the lymphomagen ethylnitrosourea these mice may present an
interesting model for short-term carcinogenicity testing. Here, we report
on the further exploration of this transgenic mouse model with two
additional carcinogens known to have, among others, the
lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and
12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week
(by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a
dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1
mice during the observation period of 40 weeks. B[a]P also induced tumours
of the forestomach within this observation period, though at a lower
incidence and apparently equally effective in wildtype and transgenic mice.
TPA, on the other hand, was unable to induce lymphomas (or tumours in any
other organ) in either transgenic or wildtype animals within the
observation period of 44 weeks, when applied dermally at the maximum
tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular
analysis showed that B[a]P-induced lymphomas in transgenic mice were of
T-cell origin, 80% of which had elevated levels of c-myc expression. None
of the lymphomas had increased N-myc expression and mutation analysis of
the ras-gene family revealed a K-ras mutation in only one out of eight
tumours investigated. Also, none of the lymphomas showed aberrant
expression of p53 as determined by immunohistochemistry. It is concluded
that the E mu-pim-1 mouse model will not be very suitable for short-term
carcinogenicity testing in general: only genotoxic chemicals that have the
lymphohaematopoietic system as target for carcinogenesis in wild- type
mice, appear to be efficiently identified.
相似文献
77.
Expression of differential nitric oxide synthase isoforms in human normal gastric mucosa and gastric cancer tissue 总被引:10,自引:2,他引:10
The present study investigated the expression and distribution of three
isoforms of nitric oxide synthase (NOS) in different anatomical regions of
the human stomach and in gastric neoplastic tissues by immunohistochemistry
using specific antibodies. Intracellular localization of individual
isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer
tissues had a marked reduction of all three NOS isoforms expression. The
expression of the endothelial NOS, neuronal NOS and inducible NOS in the
tumor tissue was significantly lower than in normal gastric mucosa (P =
0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the
expression of inducible NOS was significantly lower than the expression of
both constitutive forms of NOS (P < 0.01). There was a tendency to
higher expression of both constitutive forms of NOS in earlier stages T2 of
the tumor compared to advanced T4 tumor. In contrast, the expression of
inducible NOS was higher than in the advanced T4 tumor than in the earlier
stages T2 of the tumor. The mapping of the expression of endothelial NOS,
neuronal NOS and inducible NOS in human stomach showed higher expression of
NOS isoforms in the distal third than in the proximal third of the stomach
(P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is
greater expression of NOS in the stomach corpus and in antrum than in the
proximal third of the normal human stomach mirroring the anatomical
predilection of common pathological changes in this part of the human
stomach. Furthermore, there was loss of the expression of individual
isoenzymes in gastric neoplasms.
相似文献
78.
Wang WS; Fan FS; Hsieh RK; Chiou TJ; Lin JK; Lin TC; Yen CC; Liu JH; Hsu H; Chen PM 《Japanese journal of clinical oncology》1997,27(3):174-179
5-Fluorouracil in combination with leucovorin has been shown to be active
in therapeutic trials of metastatic colorectal carcinoma. In this study, we
administered these drugs to 72 patients with metastatic colorectal
carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil
were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and
leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36
patients with or without prior 5-fluorouracil treatment received
5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous
infusion every two weeks. Clinical efficacy and toxicity were assessed by
WHO criteria. Variables were tested for relations to response and survival
by univariate and multivariate analysis. The response rate was 19.4% in
weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527).
Median survivals in the two arms were 18.4 months (weekly) and 21 months
(biweekly) respectively (P = 0.708). Gastrointestinal side effects
including nausea, vomiting, diarrhea and mucositia were the major
toxicities of these regimens. By multivariate analysis, the only factor to
influence response rate was the site of metastases (P = 0.009). The only
factor to affect survival was performance status of the patient (P =
0.0001). We concluded that the two 5-fluorouracil based regimens are
well-tolerated and shown to have a response rate comparable with previous
reports of similar regimens in patients with metastatic colorectal cancer.
Only liver metastases seemed to have a better response to therapy.
Performance status is the most important prognostic factor in patients with
metastatic colorectal cancer.
相似文献
79.
Wang WS; Liu JH; Chiou TJ; Hsieh RK; Yen CC; Chen PM 《Japanese journal of clinical oncology》1997,27(3):180-184
A 28-year-old woman was admitted to our Hospital with a chief complaint of
progressive gingival swelling and loosening of teeth over about a year.
According to past history, she had received total thyroidectomy 2 years
previously due to thyromegaly. The thyroidectomy specimen was at first
interpreted as 'poorly differentiated carcinoma of the thyroid'. One year
ago, she began to be aware of gingival swelling and loosening of teeth. A
gum biopsy was taken and the pathologic features were similar to her
'thyroid carcinoma'. Subsequent investigations, including
immunohistochemical stain, showed the gum was heavily infiltrated with
histiocyte-like Langerhans' cells which were positive for S-100 protein.
Ultrastructural examination of the cells under electron microscope revealed
many typical intra-cytoplasmic Birbeck granules. Langerhans' cell
histiocytosis was diagnosed. Langerhans' cell histiocytosis with thyroid
involvement is extremely rare and may run a relatively indolent course.
Even on a retrospective examination, it may easily be confused with poorly
differentiated carcinoma of the thyroid. We suspect that this error may
have been made on other occasions and that the occurrence of this condition
may be underreported.
相似文献
80.
D M Tappin R P Ford K P Nelson B Price P M Macey R Dove J Larkin B Slade 《Archives of disease in childhood》1996,74(5):427-431
Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was ''regular'' were directly marked on single night records. Sleep state was determined from respiratory variables. ''Regular'' breathing was a reliable marker of ''quiet'' sleep (specificity 93%). The duration of ''quiet'' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns. 相似文献