Moulded Osteomyofascial Pedicled Split (MOPS) Craniotomy Flap in Reconstruction of Anterior Cranial Fossa Defects: Pilot Study of a Novel Technique.

INTRODUCTION: Anterior cranial fossa (ACF) defects still remains a reconstructive challenge to neurosurgeons due to the difficult location, inaccessibility, and unfavorable vascular anatomy. Usual reconstructive methods reported complications such as recurrent cerebrospinal fluid leak due to bone resorption and tissue breakdown. This is mainly due to the avascularity of the bone graft and inability to provide bony structural support for the skull base. An ideal reconstructive modality should provide a rigid bony support to prevent brain herniation as well as ensure a water tight barrier between sinonasal tract and intracranial compartment. METHODOLOGY: Hence, we thought of a novel technique of taking the outer table of the primary craniotomy flap with its intact myofascial pedicle and moulded it with multiple osteotomies (moulded osteomyofascial pedicled split (MOPS) craniotomy flap) to fit into uneven ACF defects. Advantages of our flap include (1) It is a pedicled vascularized bone flap. (2) It is taken from primary craniotomy flap; hence, no separate craniotomy is required. (3) The inner table is intact and leaves no secondary calvarial bone defect on the donor site. (4) Osteoplastic flap is moulded to fit into the defect, thus providing good contour. RESULTS: MOPS flap was used in five patients with ACF defects due to varied etiologies such as encephalocele defect, frontal mucocele, skull base meningioma, and complex naso ethmoid fracture. Age of the patients included in the study varied from 21 to 60 years. Male:female ratio was 4:1. ACF defects were reconstructed using MOPS flap in all cases. There were no postoperative complications and 1-month postoperative computerized tomography scan showed no evidence of bone resorption with acceptable cosmesis. CONCLUSION: MOPS craniotomy flap provides a novel, easily mastered, and cost-effective technique with minimal complication in reconstruction of complex ACF defects with acceptable esthetic and functional outcome.

Accuracy of the standard systematic 12-core transrectal ultrasound-guided biopsy on a prostate phantom model

OBJECTIVE@#The detection rate of the current standard systematic 12 core transrectal ultrasound (TRUS)guided prostate biopsy remains low despite numerous modifications of the technique. This non-randomized experimental study evaluated the accuracy of standard TRUS-guided systematic prostatebiopsy as performed by selected urologists in obtaining samples representative of the peripheral zoneof the prostate, by analyzing virtual biopsies performed on a prostate phantom model.@*MATERIALS AND METHODS@#Thirty (30) urologists (26 consultants and 4 senior residents) were invited toperform two consecutive simulation TRUS guided 12-core biopsies on a phantom prostate model.The task was to hit twelve equal sized spherical targets which would correspond to the lateral andextreme lateral areas of the base, mid gland and apex of the peripheral zone of the phantom prostate,which would represent the usual biopsy technique. Degree of agreement (kappa) was computed.Eight (8) operators had below satisfactory kappa values and were excluded from the succeedinganalysis. Accuracy was calculated by dividing the number of accurately hit targets by the number ofvirtual cores (12). Data were encoded in MS Excel and Stata MP v.14 was used for data analysis.@*RESULTS@#Overall, the mean accuracy was 63.17% and median accuracy was 60% (95% CI: 49.2-65.15)for the 22 operators included in the study. The lateral regions, particularly the midgland (95.8%-100% accuracy) were the most frequently biopsied areas and were often resampled. The targets at theprostatic base were missed by most operators (36.05% accuracy).@*CONCLUSION@#Systematic TRUS guided prostate biopsy, in the manner that it is performed, has itsinherent flaws, compounded by limitations in imaging capability and intra-operator variabilityresulting in low accuracy rates. A shift to newer prostate biopsy technique and methodologies withsignificantly higher accuracy rates is recommended.

Outcomes of duplex system ureteroceles in pediatric patients managed primarily with transurethral incision

@#Transurethral incision of ureterocele (TUI-U) is a simple, quick, less invasive, and less expensive,and an effective procedure for the management of ureteroceles. Several studies have already shownits utility for primary management of ureteroceles but it has also been associated with the need foradditional surgery. The authors reviewed charts of patients from their database to describe the outcomesof TUI-U done in ureteroceles associated with the upper pole moiety of a duplex system. They alsolooked into preoperative patient characteristics and post TUI-U outcomes that could influence theneed for subsequent surgeries.@*MATERIALS AND METHODS@#The authors identified patients from their duplex system database who presentedwith a ureterocele and underwent TUI-U. They reviewed the patient records of 25 patients who wereincluded in the study to determine the outcomes of TUI-U in duplex system ureteroceles. Chi squareand Mann Whitney U tests were used to determine whether preoperative patient features and postTUI-U outcomes were associated with secondary surgery.@*RESULTS@#Out of 65 patients who had duplex system ureteroceles, 25 patients (38.4%) underwent TUI-U at a mean age of 1.51 years old. TUI-U alone was successful in improving the prevalent signs andsymptoms of 15 patients (60%) in this group, while 10 patients (40%) had to undergo subsequentsurgical procedures. Breakthrough urinary tract infection (UTI) post TUI-U was the only patientfactor noted to be significantly associated with a secondary surgery for duplex system ureterocele(p=0.027).@*CONCLUSION@#TUI-U as primary treatment for duplex system ureteroceles is not yet widely accepteddue to reported rates of morbidities and need for secondary surgery. Present data however show thatTUI-U can be used as a primary procedure and even as a definitive procedure for this subset ofpatients with remarkable results in terms of symptoms resolution and improvement of upper tract profiles.

Expanding the neutralization scope of the EchiTAb-plus-ICP antivenom to include venoms of elapids from Southern Africa.

EchiTAb-plus-ICP is an antivenom prepared from plasma of horses hyperimmunized with the venoms of the carpet viper (Echis ocellatus), the puff adder (Bitis arietans) and the black-necked spitting cobra (Naja nigricollis). Therefore, the use of this antivenom has been limited to Western Africa. In order to expand the neutralization scope of EchiTAb-plus-ICP, we supplemented the immunogenic mixture with the venoms of B. arietans, the black mamba (Dendroaspis polylepis), the Mozambique spitting cobra (Naja mossambica), the snouted cobra (N. annulifera), and the rinkhals (Hemachatus haemachatus) from Swaziland. The ability of the expanded-scope antivenom, hereby named EchiTAb + ICP, to neutralize the venoms of B. arietans, D. polylepis, N. mossambica and H. haemachatus was similar to those of FAV Afrique and the SVA African antivenoms. In comparison to the SAIMR antivenom, the expanded-scope EchiTAb + ICP had lower ability to neutralize the venom of B. arietans, but similar ability to neutralize the venoms of D. polylepis, N. mossambica and H. haemachatus. Owing to its low protein concentration, the expanded-scope EchiTAb + ICP had lower ability to neutralize the venom of N. annulifera than FAV Afrique and the SAIMR antivenoms. However, when formulated at a protein concentration as high as FAV Afrique and SAIMR antivenoms, the expanded-scope EchiTAb + ICP showed similar capacity to neutralize this poorly immunogenic venom. Our results encourage the transition to the new EchiTAb + ICP antivenom, with an expanded neutralization scope that includes venoms of some of the most medically important elapids from Southern Africa. Clinical trials are required to determine the minimum effective-safe dose of the new EchiTAb + ICP for each type of envenomation.

The current status of immunotherapy in peritoneal carcinomatosis.

INTRODUCTION: Peritoneal carcinomatosis (PC) is a cancer disease with an urgent need for effective treatment. Conventional chemotherapy failed to show acceptable results. Cytoreductive surgery and hyperthermic chemoperfusion (HIPEC) are only beneficial in few patients with resectable peritoneal metastasis. Immunotherapy could be attractive against PC, as all requirements for immunotherapy are available in the peritoneal cavity. AREAS COVERED: This review analyzes the present literature for immunotherapy of PC. Advances from immune stimulators, radionucleotide-conjugated- and bispecific antibodies to future developments like adoptive engineered T-cells with chimeric receptors are discussed. The clinical development of catumaxomab, which was the first intraperitoneal immunotherapy to be approved for clinical treatment, is discussed. The requirements for future developments are illustrated. Expert commentary: Immunotherapy of peritoneal carcinomatosis is manageable, showing striking cancer cell killing. Improved profiles of adverse events by therapy-induced cytokine release, enhanced specific killing and optimal treatment schedules within multimodal treatment will be key factors.

Autoaugmentation versus enterocystoplasty: Outcomes in myelodysplastic children with neurogenic bladder

OBJECTIVE: Bladder autoaugmentation with detrusorectomy is done to improve bladder capacity and compliance in neurogenic bladders, to achieve constant low bladder pressure, preventing sequelae such as renal failure. Some reports discourage its application however citing that effects are short term and failure rates are high. We compared the pre and post-operative urodynamic profile of high risk patients undergoing autoaugmentation or enterocystoplasty to determine if it can still be used as a treatment option for neurogenic bladders. MATERIALS AND METHODS: A retrospective study using the database of our spina bifida foundation was performed. Out of 382 patients, 45 underwent augmentation cystoplasty. Twenty seven (27) had followed evaluation protocol and were included in the study. The median age was 8.6 years at the time of surgery and the median years of follow up was 3.5 years. Urodynamic parameters, as well as symptom and bladder/sphincter profiles, pre- and post-operatively were compared between the two groups. RESULTS: In the autoaugmentation group there was a 42.45% mean increase in capacity, and mean increase in compliance of 181.1% versus a 190.3% increase in capacity, and 479% increase in compliance in the enterocystoplasty group. The difference is statistically significant. There was no difference in the end filling pressure, leak point pressures, reflux, number of postoperative UTIs and incontinence. One patient in the autoaugmentation needed redo with an enterocystoplasty. Complication rates were comparable in both groups. CONCLUSION: Autoaugmentation cystoplasty is still a viable option for surgical management of neurogenic bladders. Our data showed that in patients who underwent detrusorectomy, there was improvement of urodynamic parameters, bladder and upper tract profiles, UTIs and incontinence, which were comparable to the gold standard.

Transvaginal hybrid NOTES cholecystectomy--results of a randomized clinical trial after 6 months.

INTRODUCTION: For cholecystectomy (CHE), both the needlescopic three-trocar technique with 2-3-mm instruments (needlescopic cholecystectomy (NC)) and the umbilically assisted transvaginal technique with rigid instruments (transvaginal cholecystectomy (TVC)) have been established for further reduction of the trauma remaining from laparoscopy. METHODS: To compare the further outcome of both techniques for elective CHE in female patients, we analyzed the secondary end points of a prospective randomized single-center trial (needlescopic versus transvaginal cholecystectomy (NATCH) trial; ClinicalTrials.gov Identifier: NCT0168577), in particular, satisfaction with aesthetics, overall satisfaction, abdominal pain, and incidence of trocar hernias postoperatively at both 3 and 6 months. After 3 months, the domains "satisfaction" and "pain" of the German version of the Female Sexual Function Index (FSFI-d) were additionally evaluated to detect respective complications. A gynecological control examination was conducted in all TVC patients after 6 months. RESULTS: Forty patients were equally randomized into the therapy and the control groups between February 2010 and June 2012. No significant differences were found for overall satisfaction with the surgical result, abdominal pain, sexual function, and the rate of trocar hernias. However, aesthetics were rated significantly better by TVC patients both after 3 and after 6 months (P = 0.004 and P < 0.001). There were no postoperative pathological gynecological findings. CONCLUSIONS: Following TVC, there is a significantly better aesthetic result as compared to NC, even at 3 and 6 months after the procedure. No difference was found for sexual function.

Relative lymphocyte count is a prognostic parameter in cancer patients with catumaxomab immunotherapy.

BACKGROUND: Catumaxomab (anti-EpCAM × anti-CD3) treatment in peritoneal carcinomatosis (PC) of EpCAM-positive cancers was effective in phase I and II studies. Recently, it was approved in the EU for treatment of peritoneal carcinomatosis and malignant ascites. Aim of this hypothesis-generating study was to identify predictive or prognostic biomarkers with relevance for overall survival. METHODS: 34 patients with PC in phase I/II studies with catumaxomab treatment were assessed for age, Karnofsky Index (KI), relative (RLC) and absolute lymphocyte count, relative and absolute granulocyte count, T-cell subsets, NK cells, and monocytes before catumaxomab therapy. Disease control (responder) was defined by stable disease, partial response or complete response (RECIST v1.0) >3 months or survival >6 months. Correlation analysis, Kaplan-Meier curves, ROC calculation, and multivariate regression were used for statistical analysis. RESULTS: Mean RC values significantly differed between the non-responder (14.0%) and the responder group (23.9%; p=0.001). RLC was correlated with overall survival (p=0.03). RLC of >12% defined by ROC calculation was associated with prolonged survival (p=0.035; hazard ratio of 2.775 for patients with RLC <12%). Patients with RLC >12% showed a mean survival of 15.6 versus 5.6 months in patients with RLC ≥ 12% (p=0.001). Multivariate analysis found the individual RLC before therapy (p=0.039) and the KI performance status (p=0.002) to be independent prognostic parameters. Increasing KI by 1% resulted in a risk decrease of 10.1%. Increasing RLC by 1% resulted in a risk decrease of 4.6%. Age and the extent of PC did not significantly influence survival. CONCLUSIONS: RLC and KI were identified as potential prognostic parameters for superior disease control and overall survival after catumaxomab treatment. RLC may be used as a biomarker to indicate a suitable immune status for catumaxomab therapy. The predictive impact has to be confirmed in further studies.

Appendectomy in Germany-an analysis of a nationwide survey 2011/2012.

INTRODUCTION: Although appendectomies are frequently performed and new procedural techniques have emerged, no nationwide analysis exists after the cessation of the German quality control in 2004. METHODS: One thousand eight hundred seventy surgical hospitals in Germany were asked to answer questions anonymously concerning the size of the department, applied procedural techniques, various technical details, as well as the approach to the intraoperative finding of an inconspicuous appendix. RESULTS: We received 643 questionnaires (34.4 %) for evaluation. Almost all hospitals (95.5 %) offer laparoscopic appendectomy (LA), 15.4 % offer single-port (SPA), and 2.2 % (hybrid-) NOTES technique (NA). LA is the standard procedure in 85.2 % of male and in 89.1 % for female patients. In an open procedure (OA), the appendix and mesoappendix are mostly ligated (93.8 and 91.5 %). A Veress needle and open access are employed equally for LA. In 66.6 % of LA, the appendix is divided using an Endo-GIA, the mesoappendix in 45.5 % with bipolar coagulation. Almost half of the hospitals routinely flush the site in OA and LA. In open surgery with an inconspicuous appendix but a pathological finding elsewhere in the abdomen, it is resected "en principe" in 64.7 % and in the absence of any pathological finding in 91.2 %. For laparoscopic procedures, the numbers are 54.8 and 88.4 %. CONCLUSIONS: Most German hospitals perform appendectomies laparoscopically regardless of patients' gender. Usage of an Endo-GIA is widely established. SPA has not gained much acceptance, nor is NA widely used yet. In the absence of any pathological findings in particular, the macroscopically inconspicuous appendix results in an appendectomy "en principe" in most German hospitals.

Differential expression of laminin isoforms in diabetic nephropathy and other renal diseases.

Laminin a non-collagenous glycoprotein is a major component of the renal glomerular basement membrane and mesangium. Thus far eleven distinct chains have been described, permutations of which make up 15 laminin isoforms. Laminin molecules interact with cells and other matrix molecules during organ development and differentiation. We studied the distribution of laminin isoforms in patients with type 1 diabetic nephropathy, membranous nephropathy, membranoproliferative glomerulonephritis and IgA nephropathy/ Henoch-Schönlein purpura. Immunofluorescence microscopic studies with laminin-chain-specific antibodies to the α1, α2, α5, ß1, ß2 and γ1 chains detected α2, ß1 and γ1 chain expression in the normal mesangium and α5, ß2 and γ1 in normal glomerular basement membrane. Significantly, constituents of the glomerular basement membrane, α5, ß2 and γ1 chains were overexpressed in kidneys with diabetic nephropathy. Initially the constituents of the mesangium increased commensurate with the degree of mesangial expansion and degree of diabetic nephropathy. Reduction in α2 chain intensity was observed with severe mesangial expansion and in the areas of nodular glomerulosclerosis. In addition, with late disease aberrant expression of α2 and ß2 chains was observed in the mesangium. Glomerular basement membrane in renal disease overexpressed molecules normally present in that location. In summary, the alterations in basement membrane composition in various renal diseases seem to not only reflect the balance between synthesis and degradation of normal basement membrane constituents, but also their aberrant expression.

Molecular characterization of Blastocystis isolates in the Philippines by riboprinting.

Extensive genomic polymorphism has been demonstrated among morphologically identical Blastocystis isolates. To this end, 32 Blastocystis isolates from the Philippines (12 from humans, 12 from pigs and 8 from chickens) were analyzed genetically by riboprinting or restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction (PCR) amplified small subunit rDNA. Three distinct riboprint patterns were observed from the HinfI digestion, while four patterns resulted from the RsaI digestion of Blastocystis SSU rDNA. Restriction fragment profiles between Blastocystis isolates from different hosts were generally different from each other. However, Blastocystis isolates within each host group were practically the same. Cluster analysis of the riboprint patterns revealed seven distinct groups of the Blastocystis isolates, including a zoonotic strain. These results demonstrate the genetic heterogeneity of Blastocystis in the Philippines and a support to the idea of the organism's zoonotic potential.

Glucose-induced changes in integrins and matrix-related functions in cultured human glomerular epithelial cells.

In cultured human glomerular epithelial cells (HGEC), 25 mM glucose resulted in decreased expression of alpha(3)-, alpha(2)-, and beta(1)-integrins and increased expression of alpha(5)- and alpha(v)beta(3)-integrins. This change was accompanied by decreased binding of HGEC to type IV collagen. In the presence of normal (5 mM) glucose concentration, cell binding to type IV collagen was primarily mediated by alpha(2)beta(1)- and alpha(5)beta(1)-integrins, as indicated by experiments in which cell adhesion to type IV collagen was competed by specific anti-integrin monoclonal antibodies. In the presence of high (25 mM) glucose, the upregulated alpha(5)- and alpha(v)beta(3)-integrins were mainly involved in cell binding to type IV collagen. Furthermore, high glucose decreased expression of matrix metalloproteinase-2 (MMP-2), a collagenase regulated in part by alpha(3)beta(1)-integrin, as suggested by the use of ligand-mimicking antibodies against these integrins, which resulted in release of increased amounts of MMP-2 in the culture medium. Finally, tissue inhibitor of metalloproteinase-2, the specific inhibitor of MMP-2, was upregulated in high glucose and could contribute to matrix accumulation. These changes could help explain basement membrane thickening in diabetes.

Induction of cytotoxicity against autologous tumour cells by interleukin-12: evidence for intrinsic anti-tumor immune capacity in curatively resected gastrointestinal tumour patients.

The aim of this study was to investigate the cell-mediated immune response in 14 patients undergoing curative resection for a gastrointestinal tumor by the induction of peripheral blood mononuclear cell (PBMC)-mediated immune activity against autologous tumour cells. PBMC were stimulated by interleukin-12 (IL-12; 100 IU/ml) and IL-2 (1,000 IU/ml) without contact with tumour cells for 36 h. Specific cytotoxic activity against autologous tumour cells (auTu), natural killer (NK)-sensitive cells (K562) and allogeneic tumour cells (RF48/HT29) was determined by fluorescence cytotoxicity assay. Additionally, inhibition experiments using the mononuclear antibodies (mAb) FMC16 and W6/32 against major histocompatibility complex I (MHC I) on autologous tumour cells were performed in order to determine the involvement of specific T lymphocytes. The cytotoxic activity of unstimulated PBMC did not differ between the three target cells. IL-12 caused a 3.2-fold increase in activity against auTu ( P=0.002). In contrast, after stimulation with IL-2, only a slight increase in activity was observed. After IL-12 stimulation, cytotoxic activity against auTu was 2.5- to 2.7-fold higher than the corresponding activity against K562/allogeneic tumour cells ( P=0.002/ P=0.006). After blocking of the MHC I complex on auTu by FMC 16 or W6/32 mAb, a 62.9%/74.4% reduction in the specific cytotoxicity of IL-12-stimulated PBMC was found. In summary, IL-12 induced an effective immune response against auTu, which was partly mediated by specific cytotoxic T lymphocytes (CTL). It was considered that de novo generation of this activity during 36 h incubation without antigen contact was hardly possible, but that the observed induction of effective anti-tumor cytotoxicity was rather based on the re-activation of a pre-existing immune potential from the tumour-host interaction. These findings indicate the existence of an autologous anti-tumor immune response following curative resection in patients undergoing surgery for solid tumours, which might influence the development of tumour recurrence from disseminated tumour cells. Making use of this capacity could constitute an attractive immunotherapeutical approach for curatively operated tumour patients.

Proximal tubular epithelial cell integrins respond to high glucose by altered cell-matrix interactions and differentially regulate matrixin expression.

Thickening of the tubular basement membrane (TBM) occurs in diabetic nephropathy, but the effects of high glucose on the functional aspects of proximal tubular epithelial cells are not clearly understood. In the present study, we examined the effects of elevated glucose concentrations on (a) integrin expression by human proximal tubular epithelial cells (HK-2) and integrin-mediated interactions with type IV collagen (colIV) and laminin, major components of TBM; (b) the expression of matrixins/matrix metalloproteinases (MMPs), which is regulated by integrins; and (c) the expression of tissue inhibitors of metalloproteinases (TIMPs). HK-2 cells cultured in 25 mM glucose underwent a reduction of the expression of alpha3, beta1, alpha(v)beta3, and alpha5 integrin subunits, with a concomitant increase of the alpha2 subunit, compared with cells grown in 5 mM glucose. Adhesion experiments demonstrated that high glucose led to increased cell adhesion on either colIV or laminin. Experiments of competition of adhesion using anti-integrin antibodies indicated that HK-2 cells in 5 mM glucose used mainly alpha(v)beta3 and alpha5beta1 integrins to adhere to colIV, whereas in 25 mM glucose they additionally used alpha2beta1. In the case of laminin, a beta1-mediated adhesion was observed when HK-2 cells were in 5 mM glucose, whereas in 25 mM glucose, alpha2beta1 and alpha(v)beta3 were also involved. Elevated glucose concentrations resulted in decreased expression of MMP-9 and MMP-2, whereas an increase in TIMP-1 and a decrease in TIMP-2 expression were observed. We also examined which integrins mediated the expression and secretion of matrixins MMP-2 and MMP-9. Ligation of alpha3beta1 with mAbs resulted in induction of MMP-2 expression and secretion, whereas antibody ligation of alpha(v)beta3 led to down-regulation of MMP-9. The above data implicate integrins of proximal tubular epithelial cells in the regulation of MMPs and in the development of TBM thickening in diabetic nephropathy.

Puromycin aminonucleoside suppresses integrin expression in cultured glomerular epithelial cells.

Puromycin aminonucleoside (PAN)-induced nephrosis is a well-described model of human idiopathic nephrotic syndrome, but the mechanism of PAN's effect is not completely understood. Because PAN injection into rats results in retraction of glomerular epithelial cell foot processes and glomerular epithelial cell detachment, it was hypothesized that PAN might alter the contacts between these cells and the glomerular basement membrane. The major integrin expressed by glomerular epithelial cells is alpha3beta1, which mediates attachment of these cells to extracellular matrix proteins including type IV collagen. T-SV 40 immortalized human glomerular epithelial cells were used to study PAN's effects on alpha3beta1 expression, as well as that of podocalyxin and the slit diaphragm component ZO-1. Glomerular epithelial cells were seeded into plastic flasks and allowed to attach and proliferate for 48 h. The cells were then incubated for another 48 h in media containing 0, 0.5, or 5.0 microg/ml PAN. PAN exposure resulted in dose-dependent decreases in alpha3 and beta1 expression, both at the protein level and at the mRNA level. This was accompanied by a significant decrease in the adhesion of glomerular epithelial cells to type IV collagen. PAN did not affect ZO-1 protein expression. Treatment with PAN increased the expression of podocalyxin at the protein and mRNA levels. Reduced glomerular epithelial cell expression of alpha3beta1 integrins and impaired adhesion to type IV collagen may contribute to the glomerular epithelial cell detachment from glomerular basement membrane seen in the PAN nephrosis model.

Identification of two alternatively spliced forms of human tubulointerstitial nephritis antigen (TIN-Ag).

Tubulointerstitial nephritis antigen (TIN-Ag) is a recently described basement membrane glycoprotein reactive with autoantibodies in some forms of immunologically mediated human tubulointerstitial nephritis. This report presents the complete cDNA and predicted amino acid sequences of two human TIN-Ag mRNA species referred to as TIN1 and TIN2. Translation through the open reading frames of these clones indicates the presence of a signal peptide and putative pre-propeptide. TIN1 additionally contains a characteristic laminin-like epidermal growth factor (EGF) motif and significant homology within the carboxy terminus with the cysteine proteinase family of enzymes. The EGF motif bears important similarities in the positions of cysteines with two motifs in the propeptide of von Willebrand factor. The EGF motif and part of the region that is homologous with the cysteine proteinase family are removed from the TIN2 cDNA. However, the rest of the sequence is identical in these two forms, indicating an alternatively spliced TIN-Ag mRNA product. Both forms contain putative calcium-binding sites. Secondary structure predictions strongly suggest differences between TIN1 and TIN2 leading to the hypothesis that these two forms of TIN-Ag may exhibit differences in their function. Expression studies with appropriate probes demonstrate expression mainly in the kidney and in the intestinal epithelium and lack of expression in other tissues. In the kidney, both TIN1 and TIN2 transcripts are detected, however, TIN1 appears to be the predominant form.