Clinical significance of IgG deposition in the glomerular mesangial area in patients with IgA nephropathy

Background

Immunoglobulin (Ig) A nephropathy (IgAN) is characterized by mesangial deposits of IgA1 and C3, often with co-deposits of IgG. We attempted to clarify the clinical significance of mesangial IgG deposition in patients with IgAN.

Methods

We retrospectively reviewed 57 patients who were diagnosed with IgAN on the basis of pathological examination of renal biopsy specimens obtained between October 2006 and December 2010. Subjects were divided into two groups: IgA+IgG deposition (IgA-IgG) group (n = 29) and IgA deposition alone (IgA) group (n = 28). The study outcome was complete remission (CR), defined as negative proteinuria by dipstick urinalysis and urinary erythrocytes of less than 1–4/high-power field.

Results

Proteinuria was greater in the IgA-IgG group than the IgA group (1.1 ± 0.8 vs. 0.7 ± 0.6 g/day, Mann–Whitney U test, P = 0.042). Capillary wall IgA deposits were noted more frequently in the IgA-IgG group than the IgA group (59 vs. 11 %, Fisher’s exact test, P = 0.014). During the median follow-up period of 33.3 months (range 6–55 months) in the 57 patients, we observed CR in 24 cases (42.1 %). After the start of treatment, urinary abnormalities disappeared earlier in the IgA group than in the IgA-IgG group (log rank test, P = 0.012). Cox’s regression model showed that IgG deposition reduced the hazard ratio for CR (hazard ratio 0.35; 95 % confidence interval 0.14–0.82, P = 0.014). Therefore, IgG deposition is a risk factor for persistent urinary abnormalities.

Conclusion

Mesangial IgG deposition is associated with more severe clinical features in patients with IgAN.     

Differences in vertebral,tibial, and iliac cancellous bone metabolism in ovariectomized rats

Bone histomorphometry is usually performed on the iliac bone in humans and the tibia or vertebrae in rats. Bone metabolism differences among skeletal sites may be problematic when translating experimental results from rats to humans, but data on such differences in rats are lacking. Therefore, we examined the differences in bone structure and metabolism among skeletal sites using the lumbar vertebra (LV), tibia, and iliac bone obtained from ovariectomized or sham-operated rats preoperatively and at various times from 3 days to 26 weeks postoperatively. The trabeculae were thicker in the LV, where bone metabolism was less active than at other sites, and numerous fine trabeculae were observed in the tibia, where bone metabolism was more active. The iliac bone structure and metabolism were intermediate between those of the tibia and LV. Ovariectomy induced lower bone volume and higher bone metabolism in all skeletal sites, but the changes were greatest and occurred earliest in the tibia, followed by the iliac bone and then LV. Ovariectomy caused changes in bone metabolic markers, which occurred earlier than those in bone tissue. Activation frequency (Ac.f) increased after ovariectomy. At week 26 in ovariectomized rats, Ac.f was highest in the tibia (3.13 N/year) but similar between iliac bone (0.87 N/year) and LV (1.39 N/year). Ac.f is reportedly 0.3–0.4 N/year in the iliac bone of postmenopausal women, suggesting that bone turnover in rats is several times higher than in humans. The reference values reported here are useful for translating experimental results from rats to humans.     

Antibody‐mediated rejection after ABO‐incompatible pediatric living donor liver transplantation for propionic acidemia: A case report

We herein present the case of a four‐yr‐old boy with PA who developed AMR after ABO‐incompatible LDLT despite undergoing B cell desensitization using rituximab. Although the CD19+ lymphocyte count decreased to 0.1% nine days after the administration of rituximab, he developed a high fever which was accompanied by arthralgia due to a streptococcal infection 13 days after rituximab prophylaxis. After the clearance of the infection, he underwent ABO‐incompatible LDLT 36 days after the administration of rituximab. The CD19+ lymphocyte count just prior to LDLT was 1.2%. He developed AMR five days after LDLT, and the antidonor‐type IgM and IgG antibody titers increased to 1:1024 and 1:1024, respectively. He was treated by plasma exchange, IVIG, steroid pulse therapy, and rituximab re‐administration; however, his liver dysfunction continued. Despite intensive treatment, he died due to complicated abdominal hernia, acute renal failure, and ARDS. This case suggests that a streptococcal infection may induce the activation of innate immune responses; thus, additional desensitization therapy should be considered prior to ABO‐incompatible LDLT if B cell reactivation is suspected.     

Characterization and diagnostic use of a recombinant single-chain antibody specific for the gp116 envelop glycoprotein of Yellow head virus

Yellow head virus (YHV) is an invertebrate nidovirus that can cause mass mortality of the cultured Penaeus monodon shrimp. A single-chain variable fragment (scFv) antibody directed against the gp116 envelop glycoprotein of YHV was constructed from hybridomas. Variable heavy (V(H)) and light (V(L)) chain genes were amplified from cDNA using antibody-specific primers, linked to generate a full-length gene via a standard peptide linker, ligated into the pET28a expression vector and transformed into E. coli. The expressed insoluble scFv antibody was solubilized, purified using immobilized metal affinity chromatography and rapid refolded; final yield 1-1.5 mg/l. Solid-phase non-competitive enzyme-linked immunosorbent assay (non-competitive ELISA) determined the affinity constant (K(A)) to be 3.34+/-0.38 x 10(8)l/mol. The sensitivity and specificity of scFv antibody was demonstrated by ELISA, dot blot and Western blot analysis. The detection limit determined by dot blot and indirect ELISA was 9 ng and 45 ng of purified YHV, respectively. Dot-blot assays revealed that the scFv antibody could detect YHV-infected shrimp at 24h post-infection and did not cross-react with White spot syndrome virus (WSSV) and Taura syndrome virus (TSV) proteins. The scFv antibody therefore might find application in rapid, simple and sensitive diagnostic tests to detect YHV in farmed shrimp.     

Shift of motor activation areas during recovery from hemiparesis after cerebral infarction: a longitudinal study with near-infrared spectroscopy

Motor functional recovery after stroke may be attributable to cerebral reorganization. We used near-infrared spectroscopy, which measures non-invasively the changes in oxy- and deoxy-hemoglobin concentrations in response to neural activation, for monitoring cerebral activation in stroke patients, and investigated the longitudinal changes in functional laterality of activations in the primary sensorimotor cortex during unilateral audio-paced (1 Hz) hand movement. We examined five ischemic stroke patients (4 females and 1 male, 52-67 years old) with mild to moderate hemiparesis at acute stages and chronic stages at least 1 month later. Normal subjects (3 females and 2 males, 47-63 years old) were also included. Unilateral hand movement activated predominantly the contralateral primary sensorimotor cortex in the normal subjects and the stroke patients when they moved unaffected hand. Affected hand movements activated bilateral sensorimotor cortices early after stroke (< 25 days of stroke onset), whereas the activation pattern returned toward normal at later periods (> 35 days). The contralaterality index (0.34 +/- 0.12 in normal control) was reduced at early periods (0.00 +/- 0.03, p < 0.01) after stroke, and returned to normal (0.35 +/- 0.24) as motor function recovered. These findings suggest that a transient increase in motor activation in the ipsilateral intact hemisphere within 1 month may play an important role in the recovery from motor dysfunction after stroke.     

Intraoperative bacterial contamination in total hip and knee arthroplasty is associated with operative duration and peeling of the iodine-containing drape from skin

European Journal of Orthopaedic Surgery & Traumatology - Surgical site infection (SSI) and periprosthetic joint infection are the most important problems after total hip arthroplasty (THA) and...     

Long‐term impact and clinical significance of living donor liver transplantation with respect to donor liver restoration and spleen size: A prospective study

This study aimed to evaluate postoperative long‐term liver restoration and splenic enlargement and their clinical significance in living donor liver transplantation. One hundred and sixteen donors who had donated livers more than 5 years previously accepted the invitation to participate in this study. The liver restoration rate and the splenic enlargement rate were calculated as the rate with respect to the original volume. The mean liver restoration rate was 0.99 ± 0.12 and older age was associated with a higher incidence for liver restoration rate <0.95 (P = .005), whereas type of donor operation was not. The donors with liver restoration rate <0.95 showed lower serum albumin levels than those with liver restoration rate ≥0.95. The mean splenic enlargement rate was 1.10 ± 0.16. Right lobe donors demonstrated higher splenic enlargement rate (1.14 ± 0.18) than left lobe/lateral segment donors (1.06 ± 0.13). In the donors with splenic enlargement rate ≥1.10, platelet count was not fully restored to the preoperative level. In conclusion, older age increases the risk for incomplete postoperative liver restoration, which may be associated with a decrease in albumin more than 5 years after donation. Right lobe donation poses a risk of splenic enlargement, which is associated with incomplete restoration of platelet count.