Anastomosis of TESI significantly improved postoperative weight and B12 absorption after MSBR. IAP, a marker of differentiation in intestinal epithelium, is present in TESI, and GFP labeling was accomplished.

The peribacteroid membrane (PBM) in legume root nodules is derived from plasma membrane following endocytosis of Rhizobium by fusion of newly synthesized vesicles. We studied the roles of plant Rab1p and Rab7p homologs, the small GTP‐binding proteins involved in vesicular transport, in the biogenesis of the PBM. Three cDNAs encoding legume homologs of mammalian Rab1p and Rab7p were isolated from soybean (sRab1p, sRab7p) and Vigna aconitifolia (vRab7p). sRab1p was confirmed to be a functional counterpart of yeast Ypt1p (Rab1p) by complementation of a yeast ypt1‐1 mutant. Both srab1 and vrab7 genes are induced during nodulation with the level of vrab7 mRNA being 12 times higher than that in root meristem and leaves. This induction directly correlates with membrane proliferation in nodules. Antisense constructs of srab1 and vrab7, under a nodule‐specific promoter (leghemoglobin, Lbc3), were made in a binary vector and transgenic nodules were developed on soybean hairy roots obtained through Agrobacterium rhizogenes‐mediated transformation. Both antisense srab1 and vrab7 nodules were smaller in size and showed lower nitrogenase activity than controls. The antisense srab1 nodules showed lack of expansion of infected cells, fewer bacteroids per cell and their frequent release into vacuoles. In contrast, antisense vrab7 expressing nodules showed accumulation of late endosomal structure and multivesicular bodies in the perinuclear region. These data suggest that both Rab1p and Rab7p are essential for the development of the PBM compartment in effective symbiosis.

We have examined the role that the transcription factor gut-enriched Krüppel-like factor (KLF4 or GKLF) plays in activating the enterocyte differentiation marker gene intestinal alkaline phosphatase (IAP). A yeast one-hybrid screen was used to identify proteins interacting with a previously identified cis-element (IF-III) located within the human IAP gene promoter. DNA-protein interactions were determined by using EMSA. Northern blot analysis was used to study RNA expression in human colon cancer RKO cells engineered to overexpress KLF4. Transient transfections with IAP-luciferase reporter constructs were used to characterize the mechanisms by which KLF4 activates IAP transcription. The yeast one-hybrid screen and EMSA identified KLF4 as binding to IF-III. RKO cells induced to overexpress KLF4 demonstrated a corresponding dose-dependent increase in IAP expression, and EMSA with nuclear extract from these cells confirmed that KLF4 binds to the IF-III element. Transient transfections revealed that KLF4 transactivated the IAP gene largely via a critical segment in the IAP promoter that includes the IF-III cis-element. Mutant KLF4 constructs failed to fully activate IAP. We have identified the enterocyte differentiation marker IAP as a KLF4 target gene. IAP transactivation by KLF4 is likely mediated through a critical region located within the proximal IAP promoter region.

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Though rare, pulmonary vascular complications after lung transplantation carry high mortality. In our opinion, early identification and intervention improves outcome. Intraoperative assessment by pressure gradient measurement and transoesophageal echocardiography is recommended. Despite this, mortality remains high and prevention is better than cure.

Thyroid hormone (T3) is a critical regulator of intestinal epithelial development and homeostasis, but its mechanism of action within the gut is not well understood. We have examined the molecular mechanisms underlying the T3 activation of the enterocyte differentiation marker intestinal alkaline phosphatase (IAP) gene. RT-PCR and Western blotting showed that thyroid hormone receptors TRalpha1 and TRbeta1 were expressed in human colorectal adenocarcinoma Caco-2 cells. Northern blotting detected expression of two IAP transcripts, which were increased approximately 3-fold in response to T3. Transient transfection studies with luciferase reporter plasmids carrying various internal and 5' deletion mutations of the IAP promoter localized a putative thyroid hormone response element (TRE) to a region approximately 620 nucleotides upstream (-620) of the ATG start codon. EMSAs using TRalpha1-retinoid X receptor alpha (RXRalpha) on sequential 5' and 3' single nucleotide deletions defined the TRE between -632 and -612 (5'-TTGAACTCAgccTGAGGTTAC-3'). Compared with the consensus TRE, the IAP-TRE is novel in that it contains an everted repeat of two nonamers (not hexamers) separated by three nucleotides. Neither TRalpha1 nor RXRalpha binds to the IAP-TRE; however, TRbeta1 binds to this TRE with minimal affinity. In the presence of TR and RXRalpha, only the TR-RXRalpha heterodimer binds to the IAP-TRE. Mutagenesis of either nonamer abolishes the biological activity of IAP promoter. We have thus identified a novel response element that appears to mediate the T3-induced activation of the enterocyte differentiation marker, intestinal alkaline phosphatase.

The aim of this study was to evaluate clinical outcomes after left ventricular assist device (LVAD) implantation in patients with severe pre-LVAD renal dysfunction (RD). The cohort of 165 consecutive patients implanted with HeartMate II LVADs was divided into two groups: 1) baseline glomerular filtration rate (bGFR) ≤ 40 ml/min/1.73 m (n = 30), and 2) GFR > 40 ml/min/1.73 m (n = 135). In both groups, GFR increased significantly at 1 month and then declined, remaining higher than the pre-LVAD level in the bGFR ≤ 40 group and returning back to the pre-LVAD level in the bGFR > 40 group by 1 year post-LVAD follow-up. Post-LVAD dialysis was used in 20% of the bGFR ≤ 40 patients and 7% of the bGFR > 40 patients (p = 0.02). By 3 months, 14% patients had GFR ≤ 40 ml/min/1.73 m. Grade ≥2 tricuspid regurgitation (TR) (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.23-10.28; p = 0.02) and model for end-stage liver disease-XI score ≥ 17 (OR, 4.2; 95% CI, 1.45-12.24; p = 0.01) were risk factors for severe RD at 3 months after LVAD implantation. Eight bGFR ≤ 40 patients underwent heart transplantation. Carefully selected patients with advanced heart dysfunction and bGFR ≤ 40 ml/min/1.73 m can improve kidney function with LVAD support and be able to bridge to isolated heart transplantation. Additional research is needed to refine patient selection for LVAD.

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