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1.

Background

Limited data exists demonstrating the efficacy of minimally invasive surgery (MIS) compared to median sternotomy (MS) for multiple valvular disease (MVD). This systematic review and meta-analysis aims to compare operative and peri-operative outcomes of MIS vs MS in MVD.

Methods

PubMed, Ovid, and Embase were searched from inception until August 2019 for randomized and observational studies comparing MIS and MS in patients with MVD. Clinical outcomes of intra- and postoperative times, reoperation for bleeding and surgical site infection were evaluated.

Results

Five observational studies comparing 340 MIS vs 414 MS patients were eligible for qualitative and quantitative review. The quality of evidence assessed using the Newcastle-Ottawa scale was good for all included studies. Meta-analysis demonstrated increased cardiopulmonary bypass time for MIS patients (weighted mean difference [WMD], 0.487; 95% confidence interval [CI], 0.365-0.608; P < .0001). Similarly, aortic cross-clamp time was longer in patients undergoing MIS (WMD, 0.632; 95% CI, 0.509-0.755; P < .0001). No differences were found in operative mortality, reoperation for bleeding, surgical site infection, or hospital stay.

Conclusions

MIS for MVD have similar short-term outcomes compared to MS. This adds value to the use of minimally invasive methods for multivalvular surgery, despite conferring longer operative times. However, the paucity in literature and learning curve associated with MIS warrants further evidence, ideally randomized control trials, to support these findings.
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Self-filling blind loops were created experimentally in jejunal segments of specific pathogen-free male Wistar rats, and the loop contents and mucosa were examined over an 8-week period for evaluation of the interaction between mucus and luminal bacteria. Corresponding jejunal segments from rats that did not undergo surgery were used as controls. Proliferation of anaerobic bacteria developed in the test animals by the first week after surgery. Despite anaerobic bacterial proliferation, no adherence by bacteria to the intestinal microvillus surface was observed by scanning or transmission electron microscopy. Rather, bacteria were present within the mucus layer overlying the intestinal mucosal surface. Immunoassay of goblet cell mucin demonstrated an increase in the proportion of mucin present in the intestinal lumen and a decrease in mucin levels in the jejunal mucosa. These results suggest that the interaction of bacteria with mucus is an important mechanism of protection of the mucosal surface in experimental small bowel bacterial overgrowth.  相似文献   
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BackgroundIt remains challenging to manage antibody-mediated rejection (ABMR) associated with angiotensin II type 1 receptor antibodies (AT1R-Abs) in kidney transplant recipients and the outcomes are not well defined. We describe the presentation, clinical course, and outcomes of this condition.MethodsThis retrospective study included kidney transplant recipients with AT1R-Ab levels ≥10 units/mL and biopsy-proven ABMR in the absence of significant HLA-donor-specific antibodies at the time of rejection.ResultsWe identified 13 recipients. Median creatinine (Cr) at rejection was significantly higher (2.05 mg/dL) compared with baseline (1.2 mg/dL), P = .006. After ABMR management, the difference in median Cr was not significant (1.5 mg/dL), P = .152. Median AT1R-Ab level was higher in the pretransplant sample (34.5 units/mL) compared with the level at rejection (19 units/mL) and after rejection treatment (13 units/mL); however, these differences were not significant, P = .129. Eight of the 13 recipients received antibody reduction therapy with plasmapheresis and intravenous immunoglobulin, and 5 of the 13 recipients had other therapies. After rejection management, 6 of the 13 recipients had improvement in Cr to baseline and 7 of the 13 recipients had > 50% reduction in proteinuria.ConclusionsAT1R-Ab–associated ABMR management and outcomes depend on the clinical presentation and may include antibody-reducing therapies among other therapies. Further prospective cohorts will improve recognizing and managing this condition.  相似文献   
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Feeding male Fischer F-344 rats for 5 weeks a diet containing1% orotic acid, a precursor for pyrimidine nucleotide biosynthesis,resulted in an increased incidence of -glutamyltrans-ferase(EC 2.3.2.2 [EC] ) positive foci induced by chemical carcinogens including1,2-dimethylhydrazine, diethylnitrosamine, benzo[a]pyrene, andaflatoxin B1. This unique effect of orotic acid can be accentuatedby supplying a liver cell proliferative stimulus. The enzymealtered hepatocytes have a higher labelling index (4.4%) comparedwith that of the hepatocytes in the surrounding liver (0.26%).The effect of orotic acid on the increased incidence of focicannot be attributed to either the induction of liver cell proliferationor the imposition of a preferential inhibitory effect on theproliferation of normal hepatocytes while permitting the carcinogen-modifiedhepatocytes to respond to an endogenous or exogenous liver cellproliferative stimulus and grow to form foci. Orotic acid alsodid not behave like some of the promoters of liver carcinogenesissuch as phenobarbital and polychlorinated biphenyls in thatit did not induce either the phase I or phase II componentsof hepatic drug metabolizing enzyme systems. Some of the possiblemechanisms by which orotic acid enhances the incidence of -glutamyltransferasepositive foci by carcinogens are discussed.  相似文献   
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Three commercially available brands of amikacin were investigated in a parallel study design for the assessment of comparative pharmacokinetics in pediatric oncology patients with chemotherapy-induced neutropenic febrile episode. Amikacin concentration in serum samples was determined by fluorescence polarization immunoassay method using Abbott TDx system. Computer software, PK II was used for computation of pharmacokinetic parameters of amikacin. The serum concentration of all brands nonsignificantly (p > 0.05) varied at all time points, except at 1 and 2 hrs post dosing. At 1 hr post dosing, the serum concentration of brand II varied from rest of two brands. Whereas at 2 hr following I/V infusion, brands II and I were statistically different. Highest serum concentration of 38.69 +/- 1.45 microg/ml was observed in case of brand III while brands I and II showed lower but not significantly different serum concentration values, i.e., 36.30 +/- 1.65 and 37.89 +/- 1.32 microg/ml, respectively when compared with brand I. The other pharmacokinetic parameters of 3 brands found to have non-significant difference (P < 0.05) except, t(1/2)alpha and Cl of brands I and II that deviated statistically significant (p < 0.01). The relative bioavailability of brand II and III as compared with brand I, considered as standard 86.17 and 96.86%, respectively falls within the accepted limits of +/- 20% required for the bioequivalence of any two brands. Based upon findings of the present study, all these brands may be used interchangeably in oncology patients. Further studies, however are needed to determine whether the statistically elevated Cl value in brand II is of any clinical significance.  相似文献   
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Two cases of jejunal strictures caused by Histoplasma capsulatum in AIDS patients are presented. Both patients were intravenous drug abusers. One patient, who was being treated for Pneumocystis carnii pneumonia, presented with jejunal perforation and the other presented with lower gastrointestinal bleeding and intestinal obstruction. On exploration, both patients were found to have jejunal strictures; one had intestinal perforation, and the other had intestinal obstruction with ulcers and strictures resulting in gastrointestinal bleeding. In areas where it is endemic, histoplasmosis is rarely disseminated. Dissemination is most commonly seen in immunosuppressed patients. Dissemination and extrapulmonary histoplasmosis is now included in the case definition of AIDS.  相似文献   
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OBJECTIVE: The objective of this study is to assess CT-guided percutaneous injection of fibrin glue for the management of cerebrospinal fluid leaks within the spine. CONCLUSION: Percutaneous CT-guided placement of fibrin glue can provide a treatment option for postoperative cerebrospinal fluid leaks, potentially allowing a major surgical procedure to be avoided. However, the complication of aseptic meningitis may occasionally result from this procedure.  相似文献   
10.
Aorta to pulmonary artery fistula is an uncommon and potentially fatal condition. This case is of a 48‐year‐old Caucasian male with congestive heart failure and multiple aortic valve replacement surgeries who presented with an acquired ascending aortic aneurysm to pulmonary artery fistula diagnosed using two‐dimensional transthoracic echocardiography via nonstandard imaging windows. Three‐dimensional transthoracic echocardiography using live/real time three‐dimensional color Doppler was used to assess the size of the opening of the fistula, providing additional value. This patient was surgically managed and is doing well 8 months postoperation.  相似文献   
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