605 research outputs found
Acute cholecystitis with massive upper gastrointestinal bleed: A case report and review of the literature
BACKGROUND: Cystic artery pseudoaneurysm is a rare complication following cholecystitis. Its presentation with upper gastrointestinal hemorrhage (UGIH) is even rarer. Thirteen patients with cystic artery pseudoaneurysm have been reported in the literature but only 2 of them presented with UGIH alone. CASE PRESENTATION: We report a 43-year-old woman who developed a cystic artery pseudoaneurysm following an episode of acute cholecystitis. She presented with haematemesis and melaena associated with postural symptoms. Upper gastrointestinal endoscopy revealed a duodenal ulcer with adherent clots in the first part of the duodenum. Ultrasonography detected gallstones and a pseudoaneurysm at the porta hepatis. Selective hepatic angiography showed two small pseudoaneurysms in relation to the cystic artery, which were selectively embolized. However, the patient developed abdominal signs suggestive of gangrene of the gall bladder and underwent an emergency laparotomy. Cholecystectomy with common bile duct exploration along with repair of the duodenal rent, and pyloric exclusion and gastrojejunostomy was done. CONCLUSION: This case illustrates the occurrence of a rare complication (pseudoaneurysm) following cholecystitis with an unusual presentation (UGIH). Cholecystectomy, ligation of the pseudoaneurysm and repair of the intestinal communication is an effective modality of treatment
Comparative Assessment of Transmission-Blocking Vaccine Candidates against Plasmodium falciparum
Attitudes and behaviors of Japanese physicians concerning withholding and withdrawal of life-sustaining treatment for end-of-life patients: results from an Internet survey
<p>Abstract</p> <p>Background</p> <p>Evidence concerning how Japanese physicians think and behave in specific clinical situations that involve withholding or withdrawal of medical interventions for end-of-life or frail elderly patients is yet insufficient.</p> <p>Methods</p> <p>To analyze decisions and actions concerning the withholding/withdrawal of life-support care by Japanese physicians, we conducted cross-sectional web-based internet survey presenting three scenarios involving an elderly comatose patient following a severe stroke. Volunteer physicians were recruited for the survey through mailing lists and medical journals. The respondents answered questions concerning attitudes and behaviors regarding decision-making for the withholding/withdrawal of life-support care, namely, the initiation/withdrawal of tube feeding and respirator attachment.</p> <p>Results</p> <p>Of the 304 responses analyzed, a majority felt that tube feeding should be initiated in these scenarios. Only 18% felt that a respirator should be attached when the patient had severe pneumonia and respiratory failure. Over half the respondents felt that tube feeding should not be withdrawn when the coma extended beyond 6 months. Only 11% responded that they actually withdrew tube feeding. Half the respondents perceived tube feeding in such a patient as a "life-sustaining treatment," whereas the other half disagreed. Physicians seeking clinical ethics consultation supported the withdrawal of tube feeding (OR, 6.4; 95% CI, 2.5β16.3; P < 0.001).</p> <p>Conclusion</p> <p>Physicians tend to harbor greater negative attitudes toward the withdrawal of life-support care than its withholding. On the other hand, they favor withholding invasive life-sustaining treatments such as the attachment of a respirator over less invasive and long-term treatments such as tube feeding. Discrepancies were demonstrated between attitudes and actual behaviors. Physicians may need systematic support for appropriate decision-making for end-of-life care.</p
Comparative study of the soft tissue of young Japanese-Brazilian, Caucasian and Mongoloid patients
Primary myoepithelial carcinoma of the lung: a rare entity treated with parenchymal sparing resection
Primary lung myoepithelial carcinomas are rare neoplasms arising from the salivary glands of the respiratory epithelium. Given the rare occurrences and reports of these tumors, appropriate recommendations for resection are difficult to formulate. Although classified as low-grade neoplasms, these tumors have a significant rate of recurrence and distant metastasis
Reduced Rate of Neural Differentiation in the Dentate Gyrus of Adult Dysbindin Null (Sandy) Mouse
Genetic variations in the gene encoding dysbindin has consistently been associated with schizophrenia and bipolar disorder, although little is known about the neural functions carried out by dysbindin. To gain some insight into this area, we took advantage of the readily available dysbindin-null mouse sandy (sdyβ/β) and studied hippocampal neurogenesis using thymidine analogue bromodeoxuridine (BrdU). No significant differences were found in the proliferation (4 hours) or survival (1, 4 and 8 weeks after the last BrdU injection) of progenitors in the subgranular regions of the dentate gyrus between sdyβ/β and sdy+/+ (control) mice. However, 4 weeks after the last BrdU injection, a significant reduction was observed in the ratio of neuronal differentiation in sdyβ/β when compared to that of sdy+/+ (sdy+/+ β=β87.0Β±5.3% vs. sdyβ/β β=β71.3Β±8.3%, pβ=β0.01). These findings suggest that dysbindin plays a role during differentiation process in the adult hippocampal neurogenesis and that its deficit may negatively affect neurogenesis-related functions such as cognition and mood
Progression to AIDS in South Africa Is Associated with both Reverting and Compensatory Viral Mutations
We lack the understanding of why HIV-infected individuals in South Africa
progress to AIDS. We hypothesised that in end-stage disease there is a shifting
dynamic between T cell imposed immunity and viral immune escape, which, through
both compensatory and reverting viral mutations, results in increased viral
fitness, elevated plasma viral loads and disease progression. We explored how T
cell responses, viral adaptation and viral fitness inter-relate in South African
cohorts recruited from Bloemfontein, the Free State
(nβ=β278) and Durban, KwaZulu-Natal
(nβ=β775). Immune responses were measured by
Ξ³-interferon ELISPOT assays. HLA-associated viral polymorphisms were
determined using phylogenetically corrected techniques, and viral replication
capacity (VRC) was measured by comparing the growth rate of gag-protease
recombinant viruses against recombinant NL4-3 viruses. We report that in
advanced disease (CD4 counts <100 cells/Β΅l), T cell responses narrow,
with a relative decline in Gag-directed responses (p<0.0001). This is
associated with preserved selection pressure at specific viral amino acids
(e.g., the T242N polymorphism within the HLA-B*57/5801 restricted TW10
epitope), but with reversion at other sites (e.g., the T186S polymorphism within
the HLA-B*8101 restricted TL9 epitope), most notably in Gag and suggestive
of βimmune relaxationβ. The median VRC from patients with CD4 counts
<100 cells/Β΅l was higher than from patients with CD4 counts β₯500
cells/Β΅l (91.15% versus 85.19%,
pβ=β0.0004), potentially explaining the rise in viral load
associated with disease progression. Mutations at HIV Gag T186S and T242N
reduced VRC, however, in advanced disease only the T242N mutants demonstrated
increasing VRC, and were associated with compensatory mutations
(pβ=β0.013). These data provide novel insights into the
mechanisms of HIV disease progression in South Africa. Restoration of fitness
correlates with loss of viral control in late disease, with evidence for both
preserved and relaxed selection pressure across the HIV genome. Interventions
that maintain viral fitness costs could potentially slow progression
A Viral Vectored Prime-Boost Immunization Regime Targeting the Malaria Pfs25 Antigen Induces Transmission-Blocking Activity
The ookinete surface protein Pfs25 is a macrogamete-to-ookinete/ookinete stage antigen of Plasmodium falciparum, capable of exerting high-level anti-malarial transmission-blocking activity following immunization with recombinant protein-in-adjuvant formulations. Here, this antigen was expressed in recombinant chimpanzee adenovirus 63 (ChAd63), human adenovirus serotype 5 (AdHu5) and modified vaccinia virus Ankara (MVA) viral vectored vaccines. Two immunizations were administered to mice in a heterologous prime-boost regime. Immunization of mice with AdHu5 Pfs25 at week 0 and MVA Pfs25 at week 10 (Ad-MVA Pfs25) resulted in high anti-Pfs25 IgG titers, consisting of predominantly isotypes IgG1 and IgG2a. A single priming immunization with ChAd63 Pfs25 was as effective as AdHu5 Pfs25 with respect to ELISA titers at 8 weeks post-immunization. Sera from Ad-MVA Pfs25 immunized mice inhibited the transmission of P. falciparum to the mosquito both ex vivo and in vivo. In a standard membrane-feeding assay using NF54 strain P. falciparum, oocyst intensity in Anopheles stephensi mosquitoes was significantly reduced in an IgG concentration-dependent manner when compared to control feeds (96% reduction of intensity, 78% reduction in prevalence at a 1 in 5 dilution of sera). In addition, an in vivo transmission-blocking effect was also demonstrated by direct feeding of immunized mice infected with Pfs25DR3, a chimeric P. berghei line expressing Pfs25 in place of endogenous Pbs25. In this assay the density of Pfs25DR3 oocysts was significantly reduced when mosquitoes were fed on vaccinated as compared to control mice (67% reduction of intensity, 28% reduction in prevalence) and specific IgG titer correlated with efficacy. These data confirm the utility of the adenovirus-MVA vaccine platform for the induction of antibodies with transmission-blocking activity, and support the continued development of this alternative approach to transmission-blocking malaria subunit vaccines
Arginase strongly impairs neuronal nitric oxide-mediated airway smooth muscle relaxation in allergic asthma
BACKGROUND: Using guinea pig tracheal preparations, we have recently shown that endogenous arginase activity attenuates inhibitory nonadrenergic noncholinergic (iNANC) nerve-mediated airway smooth muscle relaxation by reducing nitric oxide (NO) production β due to competition with neuronal NO-synthase (nNOS) for the common substrate, L-arginine. Furthermore, in a guinea pig model of allergic asthma, airway arginase activity is markedly increased after the early asthmatic reaction (EAR), leading to deficiency of agonist-induced, epithelium-derived NO and subsequent airway hyperreactivity. In this study, we investigated whether increased arginase activity after the EAR affects iNANC nerve-derived NO production and airway smooth muscle relaxation. METHODS: Electrical field stimulation (EFS; 150 mA, 4 ms, 4 s, 0.5 β 16 Hz)-induced relaxation was measured in tracheal open-ring preparations precontracted to 30% with histamine in the presence of 1 ΞΌM atropine and 3 ΞΌM indomethacin. The contribution of NO to EFS-induced relaxation was assessed by the nonselective NOS inhibitor N(Ο)-nitro-L-arginine (L-NNA, 100 ΞΌM), while the involvement of arginase activity in the regulation of EFS-induced NO production and relaxation was investigated by the effect of the specific arginase inhibitor N(Ο)-hydroxy-nor-L-arginine (nor-NOHA, 10 ΞΌM). Furthermore, the role of substrate availability to nNOS was measured in the presence of exogenous L-arginine (5.0 mM). RESULTS: At 6 h after ovalbumin-challenge (after the EAR), EFS-induced relaxation (ranging from 3.2 Β± 1.1% at 0.5 Hz to 58.5 Β± 2.2% at 16 Hz) was significantly decreased compared to unchallenged controls (7.1 Β± 0.8% to 75.8 Β± 0.7%; P < 0.05 all). In contrast to unchallenged controls, the NOS inhibitor L-NNA did not affect EFS-induced relaxation after allergen challenge, indicating that NO deficiency underlies the impaired relaxation. Remarkably, the specific arginase inhibitor nor-NOHA normalized the impaired relaxation to unchallenged control (P < 0.05 all), which effect was inhibited by L-NNA (P < 0.01 all). Moreover, the effect of nor-NOHA was mimicked by exogenous L-arginine. CONCLUSION: The results clearly demonstrate that increased arginase activity after the allergen-induced EAR contributes to a deficiency of iNANC nerve-derived NO and decreased airway smooth muscle relaxation, presumably via increased substrate competition with nNOS
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