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21.
A 25 year old woman developed a right pleural effusion 6 weeks after commencement of short course chemotherapy for left sided tuberculous pleural effusion. Since the patient improved following continuation of the same treatment, it is presumed to be a case of paradoxical response to anti-tuberculosis treatment. 相似文献
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23.
BACKGROUND/PURPOSE: Glial-derived growth factor (GDNF), which is the ligand of RET is reported to be essential for the development of enteric nervous system. A GDNF knockout mouse model has shown that the gastric region is a critical passing site between GDNF-RET-independent neuroblasts (colonizing the esophagus) and GDNF-RET-dependent neuroblasts (colonizing the small and large bowel). The earliest GDNF site of production is the mesenchyme and the outer smooth muscle cell (SMC) layer of the developing bowel. In the mature gastrointestinal tract the presence of GDNF is restricted to enteric glial cells. The aim of this study was to investigate the expression of GDNF and RET in infantile hypertrophic pyloric stenosis (IHPS). METHODS: Full-thickness muscle biopsy specimens were obtained from 8 IHPS patients at pyloromyotomy and from 8 age-matched controls without gastrointestinal disease. Indirect immunohistochemistry was performed using avidin-biotin-peroxidase complex method with anti-GDNF and anti-RET antibodies. Quantitative analysis was performed using sandwich-type enzyme-linked immunosorbent assay (ELISA) for GDNF. RESULTS: GDNF- and RET-positive nerve fibers were absent or markedly reduced in IHPS compared with controls. GDNF was expressed strongly by smooth muscle cells of both muscular layers in IHPS, whereas no GDNF expression was detected in pyloric muscle of controls. The quantity of total GDNF in IHPS was significantly higher than in controls (P < .01). CONCLUSIONS: The lack or markedly decreased number of GDNF-positive nerve fibers in IHPS supports the hypothesis of a selective immaturity of the enteric glia in the muscular layers in IHPS. The strong expression of GDNF in smooth muscle cells in IHPS and the increased levels of GDNF in IHPS suggest a compensatory mechanism by which the smooth muscle cells continue to produce GDNF until maturation of the enteric glial cells occurs. 相似文献
24.
Multiple gastrointestinal atresias (MGA) have been reported to account for 6% to 32% of all intestinal atresias. Controversy
exists regarding the pathogenesis. Many investigators believe MGA to be the result of multiple ischemic infarctions of the
intestinal tract. However, some have suggested that MGA results from a malformative process early in fetal life. Prenatal
exposure to adriamycin in a rat model has been reported to lead to a spectrum of tracheoesophageal and associated malformations
of the gastrointestinal tract, including intestinal atresias, identical to these observed in humans. The aim of this study
was to determine the incidence and histopathologic findings of MGA in order to understand the pathogenesis. Timed-pregnant
Sprague-Dawley rats were injected with adriamycin (1.75 mg/kg) in nine different gestational-day protocols. MGA was only seen
in those rats who received adriamycin on gestational days 7, 8, and 9. The litters were recovered on day 21 by cesarean section.
The digestive tracts (DT) of the fetuses were harvested for macroscopic and microscopic examination. Ten rats who received
adriamycin on gestational days 7, 8, and 9 produced 87 newborns; 1 was damaged during dissection. DT anomalies occurred in
80 (93%) of the 86 newborns; 94% of these demonstrated MGA. There was a very high incidence of associated anomalies in newborns
with MGA. Histologically, the blind-ending atresias showed different degrees of villous hyperplasia with or without intraluminal
material. This is the first report demonstrating a high rate of occurrence of MGA in the adriamycin rat model. The injection
of adriamycin early in gestation, the high incidence of associated malformations, and the anatomic and histologic findings
in MGA indicate that MGA is a result of a malformative rather than an ischemic process.
Accepted: 22 September 2000 相似文献
25.
Over a period of 18 years, 77 of 135 patients treated for Hirschsprung's disease (HD) presented in the neonatal period. Of these 77 patients, 8 had gastrointestinal (GI) perforations. Seven patients were born at full term and 1 at 32 weeks of gestation. Three patients had associated trisomy 21. The site of perforation included rectum in 1 patient, sigmoid in 1, descending colon in 1, transverse colon in 2, caecum in 2, and jejunum in 1. Perforations occurred in ganglionic bowel in 7 patients and in the aganglionic segment in 1. One patient died in the newborn period of overwhelming sepsis secondary to enterocolitis, and histology of the bowel confirmed HD. In 6 patients HD was confirmed on barium enema and suction rectal biopsy, and they subsequently underwent a definitive pull-through operation. The 1 patient in whom the initial barium enema was normal continued to suffer from constipation until the age of 7 years, when the diagnosis of HD was established. He then underwent a pull-through procedure with no further problems. An association between neonatal intestinal perforation and HD must therefore be recognised to avoid delay in the management.
Correspondence to: P. Puri 相似文献
26.
Naho Fujiwara Johannes Duess Prem Puri Jennifer Thompson 《Pediatric surgery international》2013,29(2):165-170
Introduction
Administration of cadmium (Cd) after 60 h (H) incubation induces ventral body wall defect (VBWD) similar to the omphalocele phenotype in the chick embryo. In this model, the earliest histological changes have been observed in somites commencing at 4-h post-treatment (4H). The molecular mechanism by which Cd acts in this critical period of embryogenesis still remains unclear. Sonic hedgehog (SHH) signalling plays an important role in vertebrate development, including somitogenesis and thus ventral body wall formation. Patched (PTCH), a cell membrane receptor for SHH, is expressed in somites and Patched knockout mice display somite dysfunction. Another transmembrane receptor, Smoothened (SMO), is also expressed in somites and transduces the SHH signal regulated by PTCH. We designed this study to test the hypothesis that SHH signalling is downregulated during the critical period of early embryogenesis in the Cd-induced omphalocele chick model.Methods
After 60 h of incubation, chicks were exposed to either chick saline or 50 μL of 50 μM cadmium acetate and divided into two groups: control and Cd (n = 24 for each group). Chicks were harvested 1, 4, and 8 h post-treatment. Real-time RT-PCR was performed to evaluate the relative mRNA expression level of SHH, PTCH and SMO. Immunofluorescence confocal microscopy was then performed to evaluate protein expression/distribution of SHH, PTCH and SMO.Results
The relative mRNA expression levels of SHH, PTCH and SMO were significantly downregulated in the Cd group compared to controls at 4H post treatment, whereas, there were no significant differences at the other time points. Immunohistochemistry revealed that the intensity of SHH, PTCH and SMO was markedly diminished at 4 h in Cd-treated embryos compared to controls.Conclusion
Disturbance of the SHH signalling pathway as evidenced by SHH, PTCH and SMO downregulation during the narrow window of early embryogenesis may result in somite maldevelopment, contributing to the omphalocele phenotype in the Cd chick model. 相似文献27.
Mukul Vij Yogesh Puri Ashwin Rammohan Gowripriya G Rajesh Rajalingam Ilankumaran Kaliamoorthy Mohamed Rela 《World journal of gastrointestinal oncology》2022,14(3):607-627
Cholangiocarcinomas are a heterogeneous group of highly aggressive cancers that may arise anywhere within the biliary tree. There is a wide geographical variation with regards to its incidence, and risk-factor associations which may include liver fluke infection, primary sclerosing cholangitis, and hepatolithiasis amongst others. These tumours are classified into intrahepatic, perihilar and distal based on their anatomical location. Morphologically, intrahepatic cholangiocarcinomas are further sub-classified into small and large duct variants. Perihilar and distal cholangiocarcinomas are usually mucin-producing tubular adenocarcinomas. Cholangiocarcinomas develop through a multistep carcinogenesis and are preceded by dysplastic and in situ lesions. While clinical characteristics and management of these tumours have been extensively elucidated in literature, their ultra-structure and tumour biology remain relatively unknown. This review focuses on the current knowledge of pathological characteristics, molecular alterations of cholangiocarcinoma, and its precursor lesions (including biliary intraepithelial neoplasia, intraductal papillary neoplasms of the bile duct, intraductal tubulopapillary neoplasms and mucinous cystic neoplasm). 相似文献
28.
29.
Rinkesh K. Bansal Narendra S. Choudhary Saurabh K. Patle Amit Agarwal Gagandeep Kaur Haimanti Sarin Rajesh Puri 《Indian journal of gastroenterology》2018,37(2):108-112
Background
Fine-needle aspiration (FNA) of adrenals is needed in patients with pyrexia of unknown origin (PUO) and adrenal enlargement in absence of other diagnostic clues. Adrenals are easily accessible by endoscopic ultrasound (EUS) due to proximity; however, there is no systemic study available on FNA of adrenals in patients with PUO. The aim of this study was to evaluate the diagnostic yield and safety of EUS-FNA of enlarged adrenal in patients with PUO.Methods
Data was analyzed from October 2010 to September 2016 at a single tertiary care center in northern India. EUS-FNA of enlarged adrenals was done in 52 patients for the etiological diagnosis of PUO in whom a definitive diagnosis could not be made with other means.Results
The mean age was 48±14 years; 36 were males and 16 were females. EUS-FNA was done from the left adrenal in 50 patients and from the right sample in 2 patients. A technical success was achieved in 100% cases. The 19-G needle was used in the majority (75%) to the presence of necrotic areas in adrenals; median numbers of passes were 2. The cytopathological diagnoses were tuberculosis (n?=?36), histoplasmosis (n?=?13), lymphoma (n?=?2), and metastasis from undiagnosed neuroendocrine tumor of lung (n?=?1). Thus, a diagnosis could be made in 52/52 (100%) patients. None of the patients had any procedure-related complications.Conclusions
EUS-FNA is a safe and effective method for evaluating etiology of PUO in patients with adrenal enlargement.30.
The pattern of sequential relapses in 10 rhesus monkeys following inoculation of sporozoites of Plasmodium cynomolgi B has been studied after administering curative dose of chloroquine (5 mg/kg base X 7 days) to eliminate blood parasitaemia after each relapse. Observation for periods ranging from 109 to 245 days showed that the interval between first six relapses was 19.3 +/- 6.77 days (1st relapse), 20.9 +/- 8.43 days (2nd relapse), 22.8 +/- 8.55 days (3rd relapse), 27.8 +/- 10.0 days (4th relapse), 31.67 +/- 11.50 days (5th relapse) and 32.5 +/- 16.26 days (6th relapse). The results of this study indicate a gradual extension of the relapse interval in successive relapses. 相似文献