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Cysteamine is approved for the treatment of cystinosis and is being evaluated for Huntington's disease and non‐alcoholic fatty liver disease. Little is known about the bioavailability and biodistribution of the drug. The aim was to determine plasma, cerebrospinal fluid (CSF), and tissue (liver, kidney, muscle) cysteamine levels following intraduodenal delivery of the drug in rats pretreated and naïve to cysteamine and to estimate the hepatic first‐pass effect on cysteamine. Healthy male rats (n = 66) underwent intraduodenal and portal (PV) or jugular (JVC) venous catheterization. Half were pretreated with cysteamine, and half were naïve. Following intraduodenal cysteamine (20 mg/kg), serial blood samples were collected from the PV or the JVC. Animals were sacrificed at specific time points, and CSF and tissue were collected. Cysteamine levels were determined in plasma, CSF, and tissue. The Cmax was achieved in 5–10 min from PV and 5–22.5 min from JVC. The PV‐Cmax (P = 0.08), PV‐AUC0–t (P = 0.16), JVC‐Cmax (P = 0.02) and JVC‐AUC0–t (P = 0.03) were higher in naive than in pretreated animals. Plasma cysteamine levels returned to baseline in ≤120 min. The hepatic first‐pass effect was estimated at 40%. Peak tissue and CSF cysteamine levels occurred ≤22.5 min, but returned to baseline levels ≤180 min. There was no difference in CSF and tissue cysteamine levels between naïve and pretreated groups, although cysteamine was more rapidly cleared in the pretreated group. Cysteamine is rapidly absorbed from the small intestine, undergoes significant hepatic first‐pass metabolism, crosses the blood brain barrier, and is almost undetectable in plasma, CSF, and body tissues 2 h after ingestion. Sustained‐release cysteamine may provide prolonged tissue exposure.  相似文献   
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To bring to light the greatly hazardous effects of the use of flue less gas geysers in the domestic setting. Over a period of two years (2008 to 2010) twenty six cases were documented as presenting with unexplained neurological events while bathing in an ill ventilated bathroom with a functional flue less gas geyser. The cases were mainly of three distinct prototypes namely seizure like episodes seen in 11 patients, carbon monoxide intoxication in 13 patients with near cardiac arrest in 4, and as a precipitating factor for epilepsy as seen in 2 cases. Out of the 13 cases presenting as carbon monoxide intoxication 4 had subtle cognitive defects and 2 developed early Parkinsonian features on follow up. To increase awareness regarding gas geyser induced epilepsy and associated carbon monoxide intoxication, both of which are entirely preventable conditions. We also wish to emphasize the importance of stringent and universal implementation of gas geyser usage and installation laws.  相似文献   
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Hypophysitis includes three histopathologically distinct entities – granulomatous, lymphocytic and xanthomatous forms. Etiopathogenesis and the immunological differences among these is not well characterized. This study aims to explore the immunopathogenesis of granulomatous and lymphocytic forms of hypophysitis. Demographic, clinical, endocrine function and radiological features of 33 histologically confirmed cases of hypophysitis were reviewed. Immunophenotyping of inflammatory component was performed in 13/33 cases. Visual disturbances (46%), headache (36%), polyuria/polydipsia (6%), menstrual disturbance (6%) and galactorrhoea (6%) were the frequent presenting symptoms. Endocrine abnormalities were noted in 11/18 cases evaluated (61%). Hypothyroidism was the most common endocrine abnormality (33.33%) followed by hyperprolactinaemia (22%) and hypocortisolism (16.66%). On neuroimaging, sellar mass with variable contrast enhancement was observed. On histology, granulomatous hypophysitis (GH) was more common (84.84%) than lymphocytic hypophysitis (LH) (15.15%). In GH, the infiltrate had almost equal proportions of CD3+ T cells and CD68+ histiocytes. Cytotoxic T cells (CD8+) predominated [CD4:CD8 < 1]. CD20+ B cell component ranged from <5% to 50%. Fibrosis, necrosis and giant cells accompanied GH. LH in contrast, had CD4+ T‐helper cell predominance [CD4: CD8 > 1]. CD68+ histiocytes constituted <20% and CD20+ B cells, 5–40% of the infiltrates. In conclusion, GH revealed cytotoxic T cell and histiocyte rich infiltrate in contrast to CD4+ T‐cell predominance in LH suggesting that the two forms have distinct immunological mechanisms in evolution, an autoimmune process in LH and type IV hypersensitivity response in GH.  相似文献   
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Burden and risk factors for wasting in the first 6 months of life among Indian children are not well documented. We used data from India's National Family Health Survey 4 to estimate the prevalence of severe wasting (weight for length < ‐3 SD) among 18,898 infants under 6 months of age. We also examined the association of severe wasting with household, maternal, and child‐related factors using multivariable logistic regression analysis. Prevalence of severe wasting among infants less than 6 months of age was 14.8%, ranging from 3.5 to 21% across states. Low birth weight (<2,500 g; adjusted odds ratio [AOR] 1.40, 95% CI [1.19, 1.65]), nonutilization of supplementary nutrition by mother during lactation (AOR 1.23, 95% CI [1.05, 1.43]), and anthropometric assessment during summer (AOR 1.37, 95% CI [1.13, 1.65]) and monsoon months (AOR 1.53, 95% CI [1.20, 1.95]) were associated with higher odds of severe wasting. Infants aged 2 to 3 months (AOR 0.78, 95% CI [0.66, 0.93]) and 4 to 5 months (AOR 0.65, 95% CI [0.55, 0.73]) had lower odds of severe wasting as compared with the 0‐ to 1‐month category. This analysis reveals a high burden of severe wasting in infants less than 6 months in India. Preventive interventions must be targeted at reducing low birth weight due to fatal growth restriction and prematurity. Appropriate care practices at facilities and postdischarge with extra attention to those born small and sick can prevent further deterioration in nutritional status.  相似文献   
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Purpose: To survey the opinion of oculoplastic surgeons on the assessment and management of lower eyelid retraction (LLR).

Methods: A web-based survey queried oculoplastic surgeon members of Ojoplast, Spanish and Brazilian Oculoplastic Societies on the management of LLR. The frequency and percentage proportions of the responses were analyzed.

Results: One hundred ninety-six oculoplastic surgeons participated in the survey. The main cause of LLR is post-blepharoplasty (62;31.6%). The most used sign to detect LLR is scleral show. The most common approaches to managing LLR are lateral canthal surgery (164/593;27.6%), autogenous spacers (148/593; 24.9%) and retractor release (131/593;22.1%). The preferred autogenous graft material includes ear cartilage (102/260;39.2%). The majority of surgeons (161/314; 51.3%) recommend massage or steroids injection (80/314;25.5%) for early post-blepharoplasty LLR, while, 54.1% (106/196) of participants suggested waiting for at least six months prior to surgical intervention. Frost suture is used after most LLR surgeries (154/196;91.1%). Incomplete correction is the main complication (111/310;35.8%) of LLR surgery. For mild LLR, 48% of the responders prefer clinical treatment; conversely, severe cases routinely require combined surgical techniques.

Conclusions: Oculoplastic surgeons frequently diagnose LLR based on scleral show. LLR management depends on the cause and severity of lid retraction. Mild cases, in general, receive clinical treatment and severe cases need a combination of surgical techniques and grafts.  相似文献   

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