Biallelic CRELD1 variants cause a multisystem syndrome, including neurodevelopmental phenotypes, cardiac dysrhythmias, and frequent infections

PURPOSE

We sought to delineate a multisystem disorder caused by recessive cysteine-rich with epidermal growth factor-like domains 1 (CRELD1) gene variants.

METHODS

The impact of CRELD1 variants was characterized through an international collaboration utilizing next-generation DNA sequencing, gene knockdown, and protein overexpression in Xenopus tropicalis, and in vitro analysis of patient immune cells.

RESULTS

Biallelic variants in CRELD1 were found in 18 participants from 14 families. Affected individuals displayed an array of phenotypes involving developmental delay, early-onset epilepsy, and hypotonia, with about half demonstrating cardiac arrhythmias and some experiencing recurrent infections. Most harbored a frameshift in trans with a missense allele, with 1 recurrent variant, p.(Cys192Tyr), identified in 10 families. X tropicalis tadpoles with creld1 knockdown displayed developmental defects along with increased susceptibility to induced seizures compared with controls. Additionally, human CRELD1 harboring missense variants from affected individuals had reduced protein function, indicated by a diminished ability to induce craniofacial defects when overexpressed in X tropicalis. Finally, baseline analyses of peripheral blood mononuclear cells showed similar proportions of immune cell subtypes in patients compared with healthy donors.

CONCLUSION

This patient cohort, combined with experimental data, provide evidence of a multisystem clinical syndrome mediated by recessive variants in CRELD1.

How effective are ionization state-based QSPKR models at predicting pharmacokinetic parameters in humans?

Optimizing the pharmacokinetics (PK) of a drug candidate to support oral dosing is a key challenge in drug development. PK parameters are usually estimated from the concentration-time profile following intravenous administration; however, traditional methods are time-consuming and expensive. In recent years, quantitative structure-pharmacokinetic relationship (QSPKR), an in silico tool that aims to develop a mathematical relationship between the structure of a molecule and its PK properties, has emerged as a useful alternative to experimental testing. Due to the complex nature of the various processes involved in dictating the fate of a drug, the development of adequate QSPKR models that can be used in real-world pre-screening situations has proved challenging. Given the crucial role played by a molecule's ionization state in determining its PK properties, this work aims to build predictive QSPKR models for PK parameters in humans using an ionization state-based strategy. We divide a high-quality dataset into clusters based on ionization state at physiological pH and build global and ion subset-based 'local' models for three major PK parameters: plasma clearance (CL), steady-state volume of distribution (VDss), and half-life (t1/2). We use a robust methodology developed in our lab entitled 'EigenValue ANalySis' that accounts for the stereospecificity in drug disposition and use the support vector machine algorithm for model building. Our findings suggest that categorizing compounds in accordance with ionization state does not result in improved QSPKR models. The narrow ranges in the endpoints along with redundancies in the data adversely affect the ion subset-based QSPKR models. We suggest alternative approaches such as elimination route-based models that account for drug-transporter interactions for CL and chemotype-specific QSPKR for VDss.

Know your neighbors: microbial recognition at the intestinal barrier and its implications for gut homeostasis and inflammatory bowel disease

Intestinal epithelial cells (IECs) perform several physiological and metabolic functions at the epithelial barrier. IECs also play an important role in defining the overall immune functions at the mucosal region. Pattern recognition receptors (PRRs) on the cell surface and in other cellular compartments enable them to sense the presence of microbes and microbial products in the intestinal lumen. IECs are thus at the crossroads of mediating a bidirectional interaction between the microbial population and the immune cells present at the intestinal mucosa. This communication between the microbial population, the IECs and the underlying immune cells has a profound impact on the overall health of the host. In this review, we focus on the various PRRs present in different cellular compartments of IECs and discuss the recent developments in the understanding of their role in microbial recognition. Microbial recognition and signaling at the epithelial barrier have implications in the maintenance of intestinal homeostasis, epithelial barrier function, maintenance of commensals, and the overall tolerogenic function of PRRs in the gut mucosa. We also highlight the role of an aberrant microbial sensing at the epithelial barrier in the pathogenesis of inflammatory bowel disease (IBD) and the development of colorectal cancer.

Alloimmunization following antigen-negative red blood cell transfusion

BACKGROUND

Red blood cell (RBC) alloimmunization can occur secondary to transfusion or pregnancy. It is observed most frequently among patients with hemoglobinopathies and myeloid neoplasms. Although previous antigen exposure is generally required for alloimmunization, some alloantibodies may develop naturally without prior exposure. Other alloantibodies may become evanescent, only to reemerge at a detectable titer following a stimulatory event. In a minute fraction of cases, 'non-naturally occurring' alloantibodies may appear without a known antigenic stimulus.

METHODS AND MATERIALS

All testing (antibody detection tests and identification, antigen phenotyping, and crossmatching) was performed using the same method and reagents, but occurred at two hospitals within the Yale New Haven Hospital delivery network, and was performed by technologists utilizing different instruments and reagent lots.

RESULTS

We present two cases of seemingly de novo alloimmunization (anti-E and anti-K), and one case of re-emergence of a known, previously evanescent alloantibody (anti-K) following transfusion of RBCs that were antigen-negative for the corresponding antibodies.

CONCLUSION

While the exact mechanism underlying the development and/or re-emergence of RBC alloantibodies in the absence of antigenic stimulation remains unclear, these cases highlight this unusual phenomenon, underscoring the general immunogenicity, as well as the potential consequences, of RBC transfusion and reiterates the importance of concluding an alloantibody specificity, even in the absence of known transfusion of RBCs with a particular antigen.

PD-1 Blockade in Mismatch Repair-Deficient, Locally Advanced Rectal Cancer

BACKGROUND

Neoadjuvant chemotherapy and radiation followed by surgical resection of the rectum is a standard treatment for locally advanced rectal cancer. A subset of rectal cancer is caused by a deficiency in mismatch repair. Because mismatch repair-deficient colorectal cancer is responsive to programmed death 1 (PD-1) blockade in the context of metastatic disease, it was hypothesized that checkpoint blockade could be effective in patients with mismatch repair-deficient, locally advanced rectal cancer.

METHODS

We initiated a prospective phase 2 study in which single-agent dostarlimab, an anti-PD-1 monoclonal antibody, was administered every 3 weeks for 6 months in patients with mismatch repair-deficient stage II or III rectal adenocarcinoma. This treatment was to be followed by standard chemoradiotherapy and surgery. Patients who had a clinical complete response after completion of dostarlimab therapy would proceed without chemoradiotherapy and surgery. The primary end points are sustained clinical complete response 12 months after completion of dostarlimab therapy or pathological complete response after completion of dostarlimab therapy with or without chemoradiotherapy and overall response to neoadjuvant dostarlimab therapy with or without chemoradiotherapy.

RESULTS

A total of 12 patients have completed treatment with dostarlimab and have undergone at least 6 months of follow-up. All 12 patients (100%; 95% confidence interval, 74 to 100) had a clinical complete response, with no evidence of tumor on magnetic resonance imaging, 18F-fluorodeoxyglucose-positron-emission tomography, endoscopic evaluation, digital rectal examination, or biopsy. At the time of this report, no patients had received chemoradiotherapy or undergone surgery, and no cases of progression or recurrence had been reported during follow-up (range, 6 to 25 months). No adverse events of grade 3 or higher have been reported.

CONCLUSIONS

Mismatch repair-deficient, locally advanced rectal cancer was highly sensitive to single-agent PD-1 blockade. Longer follow-up is needed to assess the duration of response. (Funded by the Simon and Eve Colin Foundation and others; ClinicalTrials.gov number, NCT04165772.).

Detection of SARS-CoV-2 in tissue: the comparative roles of RT-qPCR, in situ RNA hybridization, and immunohistochemistry

INTRODUCTION

The emergence of SARS-CoV-2, the causative agent the COVID-19 pandemic, has led to a rapidly expanding arsenal of molecular diagnostic assays for the detection of viral material in tissue specimens.

AREAS COVERED

We review the value and shortcomings of available tissue-based assays for SARS-CoV-2 detection in formalin-fixed paraffin-embedded (FFPE) tissue, including immunohistochemistry, in situ hybridization, and quantitative reverse transcription PCR (RT-qPCR). The validation, accuracy, and comparative utility of each method is discussed. Subsequently, we identify commercially available antibodies which render the greatest specificity and reproducibility of staining in FFPE specimens.

EXPERT OPINION

We offer expert opinion on the efficacy of such techniques and guidance for future implementation, both clinical and experimental.

Concomitant factor VIII inhibitor and lupus anticoagulant in an asymptomatic patient

Acquired hemophilia A, caused by autoantibodies that bind to and neutralize the activity of coagulation factor VIII (FVIII), almost universally presents as a severe bleeding diathesis. Lupus anticoagulants (LAs), autoantibodies directed against phospholipids or protein-phospholipid complexes, manifest clinically with an increased risk of thrombosis. While these autoantibodies are uncommon, the distinctive clinical presentation in conjunction with the typical laboratory findings often enable straightforward identification of the underlying autoantibody. However, the presence of a concomitant acquired FVIII inhibitor and LA is exceedingly rare with fewer than 20 documented cases. All prior patients presented with life-threatening hemorrhage, thrombosis, or both, prompting comprehensive hematologic evaluation and subsequent identification of the pathologic antibodies. We describe a novel case of a patient with no signs of hemorrhage or thrombosis who was incidentally found to have both a FVIII inhibitor and LA during evaluation of a prolonged partial thromboplastin time (PTT). This finding resulted in FVIII inhibitor-directed management, including immunosuppressive therapy. The unique presentation of an incidental FVIII inhibitor and LA in an asymptomatic patient without thrombotic or bleeding complications highlights the potential challenge in elucidating the etiology of a prolonged PTT, as LAs and FVIII inhibitors both prolong the PTT, and each entity can interfere with assays designed to detect the presence of the other autoantibody. This case underscores the importance of recognizing that patients with major underlying disturbances in their hematologic physiology, but in whom clinical symptoms have yet to manifest, may potentially be overlooked until such symptoms are evident.

Multiphase CT Angiography: A Useful Technique in Acute Stroke Imaging-Collaterals and Beyond

Multiphase CTA offers several important advantages over the traditional single-phase CTA technique in acute ischemic stroke, including improved detection of large-vessel occlusion, improved characterization of collateral status, improved tolerance of patient motion and poor hemodynamics, and higher interrater reliability. These benefits are gleaned at little additional cost in terms of time, risk to the patient, and capital expense. Existing data suggest that there are important benefits to using multiphase CTA in lieu of single-phase CTA in the initial vessel assessment of patients with acute stroke.

An EEG coherence-based analysis approach for investigating response conflict processes in 7 and 9-year old children

Understanding the development of the brain's neural networks can reveal critical insights into the cognitive changes that occur from infancy to late childhood. Behavioural metrics including: task accuracy, stimuli recognition, and reaction time show dramatic changes over childhood. In this study we investigated response control using the Erikson Flanker task. In a dataset of 45 EEG recordings, we calculated spectral coherence to measure connectivity between all possible electrode pairs. Coherence measures were performed on two different trial conditions -congruent (where there is no response conflict) and incongruent (where response conflict is induced). The increase in incongruent coherence compared to the congruent was investigated for each electrode pair over 45 healthy subjects aged seven years. The same calculation was then performed on the same group of subjects two years later when they were aged nine years. The results revealed that at age seven years, increased coherence was detected in the left prefrontal to right and left parieto-occipital - i.e. an anatomical region located between the parietal and occipital lobes - within theta band. No increase was found for the older group-at age nine years- which may indicate cognitive development in conflict processing mechanism.

In vitro Inhibitory Effect of Gymnema sylvestre Extracts and Total Gymnemic Acids Fraction on Select Cytochrome P450 Activities in Rat Liver Microsomes

BACKGROUND AND OBJECTIVES

Gymnema sylvestre R. Br. is a well-known Indian medicinal herb. Gymnemic acids are pentacyclic triterpenes saponins and active phytoconstituents of Gymnema sylvestre. The study aimed at evaluation of the in vitro rat liver cytochrome P450 (CYP) inhibition potential of extracts and total gymnemic acid (TA)-enriched fractions from G. sylvestre.

METHODS

Standardization of G. sylvestre [ethanolic (EL), hydroethanolic (HE), total acid of ethanolic (TAE), total acid of hydroethanolic (TAHE) and total acid of aqueous (TAAQ) extract] was done with respect to deacyl gymnemic acid (DAGA), using reverse phase-high performance liquid chromatography (RP-HPLC). Total triterpenoid content was determined by vanillin perchloric acid assay.

RESULTS

Total triterpene content was found to be the highest in TAAQ (59.86 ± 0.005% w/w) and TAE (49.77 ± 0.009% w/w). TAAQ showed IC₅₀ ≤ 50 µg/ml for all selected CYP activities. Testosterone 6β-hydroxylation was strongly inhibited by TAE (IC₅₀: 15.48 ± 2.13 µg/ml) and was moderately by TAAQ and EL with IC₅₀ ≥ 50 µg/ml. Flurbiprofen 4'-hydroxylation was subject to strong, weak and moderate inhibition by TAAQ (IC₅₀: 34.67 ± 1.38 µg/ml), TAE (IC₅₀: ≥ 50 µg/ml) and EL (IC₅₀: > 50 µg/ml), respectively. Dextromethorphan O-demethylation was inhibited by TAHE and TAAQ.

CONCLUSIONS

In vitro inhibition studies suggested that TA strongly inhibits activity of selected CYP. This inhibition may possibly be due to triterpenoids and gymnemic acids that have been reported to be present in it. Data also suggest a potential for possible in vivo herb-drug interactions involving G. sylvestre and other medications that are metabolized by the same CYP.

Response conflict processes' classification in 7 and 9 year old children using EEG brain connectivity measures

Investigating cognitive development of children poses interesting challenges pertaining to emergence of children's' ability to think and understand. Psychological tasks that involve conflict, like the Flanker task, are widely used to understand development of response conflict processes. In this study, EEG signals were used to examine the coherence and imaginary part of coherency within the delta, theta, alpha and beta bands across different conditions of the Flanker task. Longitudinal data were collected from a group of typically developing children at ages of seven and nine. We found that the imaginary part of coherency was more helpful in distinguishing between stimuli - alpha and beta bands resulted in 90.90% classification rate in seven year old children. The beta and theta bands were found to be more effective for stimuli classification in nine year old children - more than 84.09% classification accuracy was achieved.

A Novel Folate-Targeted Nanoliposomal System of Doxorubicin for Cancer Targeting

Targeted drug delivery systems for cancer improves anti-tumor efficacy and reduces systemic toxicity by restricting availability of cytotoxic drugs within tumors. Targeting moieties, such as natural ligands (folic acid, transferrin, and biotin) which are overexpressed on tumors, have been used to enhance liposome-encapsulated drug accumulation within tumors and resulted in better control. In this report, we explored the scope of targeting ligand folic acid, which is incorporated in liposome systems using folic acid-modified cholesterol (CPF), enabled highly selective tumor-targeted delivery of liposome-encapsulated doxorubicin and resulted in increased cytotoxicity within tumors. Folate-tagged poloxamer-coated liposomes (FDL) were found to have significantly higher cellular uptake than conventional poloxamer-coated liposomes (DL), as confirmed by fluorometric analysis in B16F10 melanoma cells. Biodistribution study of the radiolabeled liposomal system indicated the significantly higher tumor uptake of FDL as compared to DL. Anti-tumor activity of FDL against murine B16F10 melanoma tumor-bearing mice revealed that FDL inhibited tumor growth more efficiently than the DL. Taken together, the results demonstrated the significant potential of the folate-conjugated nanoliposomal system for drug delivery to tumors.

Optical Characterization of Commercial Lithiated Graphite Battery Electrodes and in Situ Fiber Optic Evanescent Wave Spectroscopy

Optical characterization of graphite anodes in lithium ion batteries (LIB) is presented here for potential use in estimating their state of charge (SOC). The characterization is based on reflectance spectroscopy of the anode of commercial LIB cells and in situ optical measurements using an embedded optical fiber sensor. The optical characterization of the anode using wavelengths ranging from 500 to 900 nm supports the dominance of graphite over the solid electrolyte interface in governing the anode's reflectance properties. It is demonstrated that lithiated graphite's reflectance has a significant change in the near-infrared band, 750-900 nm, compared with the visible spectrum as a function of SOC. An embedded optical sensor is used to measure the transmittance of graphite anode in the near-infrared band, and the results suggest that a unique inexpensive method may be developed to estimate the SOC of a LIB.

Notch1 endocytosis is induced by ligand and is required for signal transduction

The Notch signalling pathway is widely utilised during embryogenesis in situations where cell-cell interactions are important for cell fate specification and differentiation. DSL ligand endocytosis into the ligand-expressing cell is an important aspect of Notch signalling because it is thought to supply the force needed to separate the Notch heterodimer to initiate signal transduction. A functional role for receptor endocytosis during Notch signal transduction is more controversial. Here we have used live-cell imaging to examine trafficking of the Notch1 receptor in response to ligand binding. Contact with cells expressing ligands induced internalisation and intracellular trafficking of Notch1. Notch1 endocytosis was accompanied by transendocytosis of ligand into the Notch1-expressing signal-receiving cell. Ligand caused Notch1 endocytosis into SARA-positive endosomes in a manner dependent on clathrin and dynamin function. Moreover, inhibition of endocytosis in the receptor-expressing cell impaired ligand-induced Notch1 signalling. Our findings resolve conflicting observations from mammalian and Drosophila studies by demonstrating that ligand-dependent activation of Notch1 signalling requires receptor endocytosis. Endocytosis of Notch1 may provide a force on the ligand:receptor complex that is important for potent signal transduction.

Assessment of regional ventilation and deformation using 4D-CT imaging for healthy human lungs during tidal breathing

This study aims to assess regional ventilation, nonlinearity, and hysteresis of human lungs during dynamic breathing via image registration of four-dimensional computed tomography (4D-CT) scans. Six healthy adult humans were studied by spiral multidetector-row CT during controlled tidal breathing as well as during total lung capacity and functional residual capacity breath holds. Static images were utilized to contrast static vs. dynamic (deep vs. tidal) breathing. A rolling-seal piston system was employed to maintain consistent tidal breathing during 4D-CT spiral image acquisition, providing required between-breath consistency for physiologically meaningful reconstructed respiratory motion. Registration-derived variables including local air volume and anisotropic deformation index (ADI, an indicator of preferential deformation in response to local force) were employed to assess regional ventilation and lung deformation. Lobar distributions of air volume change during tidal breathing were correlated with those of deep breathing (R(2) ≈ 0.84). Small discrepancies between tidal and deep breathing were shown to be likely due to different distributions of air volume change in the left and the right lungs. We also demonstrated an asymmetric characteristic of flow rate between inhalation and exhalation. With ADI, we were able to quantify nonlinearity and hysteresis of lung deformation that can only be captured in dynamic images. Nonlinearity quantified by ADI is greater during inhalation, and it is stronger in the lower lobes (P < 0.05). Lung hysteresis estimated by the difference of ADI between inhalation and exhalation is more significant in the right lungs than that in the left lungs.

In silico optimization of pharmacokinetic properties and receptor binding affinity simultaneously: a 'parallel progression approach to drug design' applied to β-blockers

The present work exploits the potential of in silico approaches for minimizing attrition of leads in the later stages of drug development. We propose a theoretical approach, wherein 'parallel' information is generated to simultaneously optimize the pharmacokinetics (PK) and pharmacodynamics (PD) of lead candidates. β-blockers, though in use for many years, have suboptimal PKs; hence are an ideal test series for the 'parallel progression approach'. This approach utilizes molecular modeling tools viz. hologram quantitative structure activity relationships, homology modeling, docking, predictive metabolism, and toxicity models. Validated models have been developed for PK parameters such as volume of distribution (log Vd) and clearance (log Cl), which together influence the half-life (t1/2) of a drug. Simultaneously, models for PD in terms of inhibition constant pKi have been developed. Thus, PK and PD properties of β-blockers were concurrently analyzed and after iterative cycling, modifications were proposed that lead to compounds with optimized PK and PD. We report some of the resultant re-engineered β-blockers with improved half-lives and pKi values comparable with marketed β-blockers. These were further analyzed by the docking studies to evaluate their binding poses. Finally, metabolic and toxicological assessment of these molecules was done through in silico methods. The strategy proposed herein has potential universal applicability, and can be used in any drug discovery scenario; provided that the data used is consistent in terms of experimental conditions, endpoints, and methods employed. Thus the 'parallel progression approach' helps to simultaneously fine-tune various properties of the drug and would be an invaluable tool during the drug development process.

Evaluation of cytochrome P450 2D6 phenotyping in healthy adult Western Indians

Background:

Cytochrome P450 2D6 (CYP2D6) metabolizes around 25% of the drugs used in therapeutics and different polymorphisms have been identified in various populations. This study aimed at finding the prevalence of CYP2D6 polymorphisms using dextromethorphan as a probe drug.

Materials and Methods:

Healthy participants were administered 60 mg dextromethorphan after an overnight fast and 5 ml of blood was collected 3 h postdose. A validated laboratory method was used to measure both dextromethorphan and its active metabolite, dextrorphan from plasma. Metabolic ratio (MR) of dextromethorphan to dextrorphan was calculated for each of the participants. Probit analysis was done and antimode was defined. Individuals with log MR equal to or higher than the antimode were classified as poor metabolizers (PMs) and those with values less than antimode were categorized as extensive metabolizers (EMs).

Results:

Data from a total of 149 participants were evaluated and the median (range) of MR was 0.25 (0.03-3.01). The polynomial equation obtained in probit analysis gave an antimode for MR of 1.39. Five (3.36%) participants were PMs and 144 (96.64%) were found to be EMs. One participant had reported mild drowsiness 2 h postdose that subsided spontaneously without any intervention.

Conclusion:

The prevalence of CYP2D6 polymorphism in Western Indian population is low (3.36%) and is similar to other populations.

Intestinal transplant registry report: global activity and trends

The Registry has gathered information on intestine transplantation (IT) since 1985. During this time, individual centers have reported progress but small case volumes potentially limit the generalizability of this information. The present study was undertaken to examine recent global IT activity. Activity was assessed with descriptive statistics, Kaplan-Meier survival curves and a multiple variable analysis. Eighty-two programs reported 2887 transplants in 2699 patients. Regional practices and outcomes are now similar worldwide. Current actuarial patient survival rates are 76%, 56% and 43% at 1, 5 and 10 years, respectively. Rates of graft loss beyond 1 year have not improved. Grafts that included a colon segment had better function. Waiting at home for IT, the use of induction immune-suppression therapy, inclusion of a liver component and maintenance therapy with rapamycin were associated with better graft survival. Outcomes of IT have modestly improved over the past decade. Case volumes have recently declined. Identifying the root reasons for late graft loss is difficult due to the low case volumes at most centers. The high participation rate in the Registry provides unique opportunities to study these issues.

Notch4 reveals a novel mechanism regulating Notch signal transduction

Notch4 is a divergent member of the Notch family of receptors that is primarily expressed in the vasculature. Its expression implies an important role for Notch4 in the vasculature; however, mice homozygous for the Notch4(d1) knockout allele are viable. Since little is known about the role of Notch4 in the vasculature and how it functions, we further investigated Notch4 in mice and in cultured cells. We found that the Notch4(d1) allele is not null as it expresses a truncated transcript encoding most of the NOTCH4 extracellular domain. In cultured cells, NOTCH4 did not signal in response to ligand. Moreover, NOTCH4 inhibited signalling from the NOTCH1 receptor. This is the first report of cis-inhibition of signalling by another Notch receptor. The NOTCH4 extracellular domain also inhibits NOTCH1 signalling when expressed in cis, raising the possibility that reported Notch4 phenotypes may not be due to loss of NOTCH4 function. To better address the role of NOTCH4 in vivo, we generated a Notch4 null mouse in which the entire coding region was deleted. Notch4 null mice exhibited slightly delayed vessel growth in the retina, consistent with our novel finding that NOTCH4 protein is expressed in the newly formed vasculature. These findings indicate a role of NOTCH4 in fine-tuning the forming vascular plexus.

Defluoridation techniques implemented by the government of karnataka, india - the current situation

INTRODUCTION

Karnataka is an Indian state which has regions with endemic fluorosis.

OBJECTIVE

To assess the various defluoridation techniques and units implemented by the Government of Karnataka, along with the cost of installation, maintenance and repair, to mitigate the problem of fluorosis.

METHODS

Information regarding the various defluoridation units was obtained from the Panchyath Raj Engineering office before they were visited. Local authorities and residents were interviewed regarding the reasons behind the success or failure of the units.

RESULTS

Of the 100 reverse osmosis units installed, 77% are defunct, only one of the two state-of-the-art solar-based technique units is currently functioning but none of the activated alumina or Nalgonda technique units.

CONCLUSION

Defluoridation units suitable for Indian conditions and operation by unskilled villagers have yet to be developed.

Evaluation of cranial capacity by mustard seed technique

The volume of the cranium is used as a rough indicator of the size of the brain. In the present study Breitinger's mustard seeds technique was applied for the measurement of cranial capacity. Grossly normal 75 male skulls of Gujarat population were studied at Kesar SAL Medical College, Ahmedabad (Gujarat) in the year 2010. The mean cranial capacity among the study group was recorded to be 1256 cc with a minimum of 1110 cc and maximum of 1430 cc. The results were compared with the similar studies by different authors from different geographical areas.

Anti-lymphocyte therapy successfully controls late "cholestatic" rejection in pediatric liver transplant recipients

Rejection is independently associated with liver graft loss in children. We report the successful rescue of grafts using ATG+/-OKT3 in late rejection associated with cholestasis. Retrospective chart review was performed after IRB approval. Between 2003 and 2010, 14 pediatric liver transplant recipients received anti-lymphocyte treatment for "cholestatic" rejection. Median age at transplantation was 12.7 yr (range 0.9-23.4), eight were boys, and immunosuppression was tacrolimus based. Median time from transplantation to rejection was five yr (range 1.1-10.5). Median peak total bilirubin was 11.1 mg/dL (range 1.4-18). All showed moderate to severe acute rejection and hepatocellular cholestasis on histology. ATG/OKT3 was started as first-line therapy in six and in the remaining eight as second-line therapy after failure of pulse steroids. Thirteen responded with normalization of aminotransferases and bilirubin, median time 16 wk (range 7-112); one non-adherent recipient has still not achieved normal graft function at last follow-up. Patient survival is 100%, with no re-transplantation and no post-transplant lymphoproliferative disease, median follow-up 2.9 yr (range 1.1-7.2). Cholestasis associated with acute rejection occurring late after liver transplantation may herald steroid resistance. First-line therapy with anti-lymphocyte preparations, prophylactic anti-microbial therapy, and close monitoring allow excellent rates of patient and graft survival.

Cytotoxicity of Ni from Surface-Treated Porous Nitinol (PNT) on Osteoblast Cells

The leaching of nickel from the surface of porous Nitinol (PNT) is mainly dependent on its surface characteristics, which can be controlled by appropriate surface treatments. In this investigation, PNT was subjected to two surface treatments, namely, water-boiling and dry-heating passivations. Phosphate buffer saline (PBS) solutions obtained from cyclic potentiodynamic polarization tests on PNT were employed to assess the cytotoxicity of Ni contained therein on osteoblast cells by Sulforhodamine B (SRB) assay. In addition, similar concentrations of Ni were added exogenously to cell culture media to determine cytotoxic effects on osteoblast cells. The morphologies of the untreated and the surface-treated PNTs were examined using SEM and AFM. Furthermore, growth of human osteoblast cells was observed on the PNT surfaces.

Outcome of combined liver and kidney transplantation in hepatitis C: a single-center long-term follow-up experience

INTRODUCTION

Hepatitis C (HCV) cirrhosis is the prevalent liver disease requiring liver transplantation in the United States. Candidates who also have end-stage renal disease, chronic renal disease stage 4, or prolonged hepatorenal syndrome are considered for combined liver and kidney transplantation (CLKT).

MATERIALS AND METHODS

We performed a retrospective study of HCV(+) and HCV(-) CLKT patients with more than 12 months of follow-up and HCV(+) patients with isolated liver transplant (OLT) to compare the outcomes of various groups.

RESULTS

Since 1988, 2983 OLTs were performed at our institution including 58 CLKTs. Of these, 23 were HCV(+) subjects who were significantly older than HCV(-) CLKT patients. Race, pretransplant dialysis time, renal indication for CLKT, Model for End-stage Liver Disease score, donor age, liver and kidney rejection as well as occurrence of posttransplant hypertension were similar among HCV(+) and HCV(-) CLKT patients. Posttransplant diabetes was observed in 80% of the HCV(+) group and 30% of the HCV(-) group (P = .01). Renal function seemed to be better in HCV(-) when compared with HCV(+) subjects at 5 years (P = .09). Overall patient survival for HCV(+) CLKT, HCV(-) CLKT, and HCV(+) OLT groups at 1, 2, and 5 years were not significantly different (P = .6).

CONCLUSION

HCV positivity should not exclude appropriate candidates for CLKT.

CoMFA and CoMSIA studies of angiotensin (AT1) receptor antagonists

Two 3D-QSAR methods--CoMFA and CoMSIA--were applied to a set of 38 angiotensin receptor (AT1) antagonists. The conformation and alignment of molecules were obtained by a novel method - consensus dynamics. The representation of biological activity, partial charge formalism, absolute orientation of the molecules in the grid, and grid spacing were also studied for their effect on the CoMFA models. The models were thoroughly validated through trials using scrambled activities and bootstrapping. The best CoMFA model had a cross-validated correlation coefficient ( q2) of 0.632, which improved with "region focusing" to 0.680. This model had a "predictive" r2 of 0.436 on a test series that was unique and with little representation in the training set. Although the "predictive" r2 of the best CoMSIA model, which included steric, electrostatic, and hydrogen bond acceptor fields was higher than that of the best CoMFA model, the other statistical parameters like q2, r2, F value, and s were unsatisfactory. The contour maps generated using the best CoMFA model were used to identify the structural features important for biological activity in these compounds.

Long-term results of intestinal transplantation for pseudo-obstruction in children

PURPOSE

The aim of this study was to determine long-term results of intestinal transplantation in children with pseudo-obstruction, particularly when stomach and colon are not part of the allograft.

METHODS

The authors conducted a case-record review of all children who underwent transplantation at our center for a primary diagnosis of pseudo-obstruction. Supplementary information was obtained from outpatient charts, computerized database, and telephone survey of parents.

RESULTS

Six small bowel and 3 liver-small bowel transplants were carried out in 8 patients between 1993 and 1999. Median follow-up is 40 months (range, 13 to 73 months). Median age at transplantation was 2.7 years (range, 0.7 to 12.8 years). Median graft survival in this series is 15 months (range, 1 day to 71 months). Stomach and colon were excluded from all allografts. Two children died 5 and 368 days after transplant and 2 graft losses occurred in 1 patient. Two children had lymphoproliferative disease; both are alive with functioning grafts. Five survivors with functioning grafts receive full enteral feedings at home. Four of the 5 have had ileostomies closed, and 3 have normal bowel movements.

CONCLUSIONS

Intestinal transplantation without stomach or colon provides children with chronic intestinal pseudo-obstruction with a good quality of life. The underlying disease poses special challenges in management.

5,6-Dihydropyran-2-ones possessing various sulfonyl functionalities: potent nonpeptidic inhibitors of HIV protease

On the basis of previous SAR findings and molecular modeling studies, a series of compounds were synthesized which possessed various sulfonyl moieties substituted at the 4-position of the C-3 phenyl ring substituent of the dihydropyran-2-one ring system. The sulfonyl substituents were added in an attempt to fill the additional S(3)' pocket and thereby produce increasingly potent inhibitors of the target enzyme. Racemic and enantiomerically resolved varieties of selected compounds were synthesized. All analogues in the study displayed decent binding affinity to HIV protease, and several compounds were shown to possess very good antiviral efficacy and safety margins. X-ray crystallographic structures confirmed that the sulfonamide and sulfonate moieties were filling the S(3)' pocket of the enzyme. However, the additional substituent did not provide improved enzymatic inhibitory or antiviral activity as compared to the resolved unsubstituted aniline. The addition of the sulfonyl moiety substitution does not appear to provide favorable pharamacokinectic parameters. Selected inhibitors were tested for antiviral activity in clinical isolates and exhibited similar antiviral activity against all of the HIV-1 strains tested as they did against the wild-type HIV-1. In addition, the inhibitors exhibited good antiviral efficacies against HIV-1 strains that displayed resistance to the currently marketed protease inhibitors.

Nonpeptidic HIV protease inhibitors: 6-alkyl-5,6-dihydropyran-2-ones possessing a novel and achiral 3-(2-t-butyl-5-methyl-4-sulfamate)phenylthio moiety

Dihydropyran-2-ones possessing a sulfamate moiety at the 4-position of the thiophenyl ring were designed to reach S3' pocket of the HIV protease. Synthetic routes for the preparation of thiotosylates possessing 3-(2-t-butyl-5-methyl-4-sulfamate) phenylthio moiety were established. SAR of various sulfamate analogs including HIV protease binding affinities, antiviral activities and therapeutic indices will be described.

Nonpeptidic HIV protease inhibitors: 6-alkyl-5,6-dihydropyran-2-ones possessing achiral 3-(4-amino/carboxamide-2-t-butyl,5-methylphenyl thio) moiety: antiviral activities and pharmacokinetic properties

Dihydropyran-2-ones possessing amino and carboxamide functionalities on 3-SPh (2-tert-butyl, 5-methyl) ring were synthesized and evaluated for their antiviral activities. Both the enantiomers of inhibitor 15 were synthesized. The in vitro resistance profile, inhibitory activities against cytochrome P450 isozymes and pharmacokinetic properties of inhibitor 15S will be discussed.

The role of phytosterols in the pathogenesis of liver complications of pediatric parenteral nutrition

Long-term parenteral nutrition of infants who have had major gut resections is associated with a high incidence of cholestatic liver disease. Affected infants have high plasma concentrations of phytosterols--compounds that resemble cholesterol but have an alkylated side chain. The phytosterols that accumulate in patients receiving parenteral nutrition are derived from the soya oil and/or soya lecithin used to make the intravenous lipid emulsion. There is a striking association between phytosterolemia and cholestatic liver disease. This has led us to put forward the hypothesis that phytosterols can cause cholestasis in susceptible infants. Experiments using neonatal piglets indicate that phytosterols (given without any of the other components of parenteral nutrition) can indeed reduce bile flow. We suggest that increasing the content of phytosterols in cell membranes may interfere with the function of important transport proteins involved in the secretion of bile. Other factors that might contribute to cholestasis (such as inhibition of cholesterol 7 alpha-hydroxylase) are discussed.

Sequence and analysis of the human ABL gene, the BCR gene, and regions involved in the Philadelphia chromosomal translocation

The complete human BCR gene (152-141 nt) on chromosome 22 and greater than 80% of the human ABL gene (179-512 nt) on chromosome 9 have been sequenced from mapped cosmid and plasmid clones via a shotgun strategy. Because these two chromosomes are translocated with breakpoints within the BCR and ABL genes in Philadelphia chromosome-positive leukemias, knowledge of these sequences also might provide insight into the validity of various theories of chromosomal rearrangements. Comparison of these genes with their cDNA sequences reveal the positions of 23 BCR exons and putative alternative BCR first and second exons, as well as the common ABL exons 2-11, respectively. Additionally, these regions include the alternative ABL first exons 1b and 1a, a new gene 5' to the first ABL exon, and an open reading frame with homology to an EST within the BCR fourth intron. Further analysis reveals an Alu homology of 38.83 and 39.35% for the BCR and ABL genes, respectively, with other repeat elements present to a lesser extent. Four new Philadelphia chromosome translocation breakpoints from chronic myelogenous leukemia patients also were sequenced, and the positions of these and several other previously sequenced breakpoints now have been mapped precisely, although no consistent breakpoint features immediately were apparent. Comparative analysis of genomic sequences encompassing the murine homologues to the human ABL exons 1b and 1a, as well as regions encompassing the ABL exons 2 and 3, reveals that although there is a high degree of homology in their corresponding exons and promoter regions, these two vertebrate species show a striking lack of homology outside these regions.

The complete nucleotide sequences of the SacBII Kan domain of the P1 pAD10-SacBII cloning vector and three cosmid cloning vectors: pTCF, svPHEP, and LAWRIST16

The complete nucleotide sequence of the 16,009-bp SacBII Kan domain of the P1 pAD10-SacBII cloning vector and the sequences of three cosmid cloning vectors, pTCF (7941 bp), svPHEP (9201 bp), and LAWRIST16 (5194 bp) have been determined. A modified diatomaceous earth (Prep-A-Gene)-based procedure, which rapidly yields highly supercoiled double-stranded DNA from recombinant P1 and cosmid clones suitable for generating shotgun libraries, also has been developed. The isolated recombinant DNAs were physically sheared to generate 1- to 2-kb fragments that then were blunt-ended and subcloned into double-stranded pUC-based sequencing vectors. The double-stranded sequencing templates were isolated by an alkaline lysis method and subjected to Taq polymerase catalyzed fluorescent end-labeled primer cycle sequencing. After shotgun sequence assembly, contig gaps were closed and ambiguities were resolved via Sequenase catalyzed fluorescent dye-terminator sequencing.

Endogenous opioids and TSH secretion in azotemic male rats

The role of endogenous opioids in the control of thyroid-stimulating hormone (TSH) secretion in uremic male rats was investigated using the narcotic antagonist naloxone. In order to eliminate the effect of weight loss due to uremia-induced anorexia as a cause of altered TSH secretion in uremia, we also studied a group of normal control animals who were pair-fed with the uremic animals, so that their weights were comparable to that of the uremic animals. Naloxone administration produced a significant increase in the basal concentration of TSH response to TRH (5 micrograms i.v.) was significantly blunted in the uremic animals compared to the normal controls and the starved animals. Naloxone administration did not alter the peak thyrotropin-releasing hormone (TRH) stimulated TSH response in any of the experimental groups of rats. Because of the possibility that the effects of naloxone on TSH secretion in the uremic rats were related to impaired clearance of the naloxone in those animals, an additional group of normal rats was given twice the dose of naloxone administered to the uremic animals. The higher dose of naloxone was similarly without effect on the basal or TRH-stimulated TSH secretion in this group. The data suggest that experimental renal failure is associated with diminished sensitivity of the thyrotroph to TRH stimulation and that this blunted sensitivity cannot be abolished by blockade of endogenous opioids by naloxone. Opioid blockade does, however, increase basal TSH secretion in uremic animals, suggesting an increase in endogenous opioidergic tone in uremia.(ABSTRACT TRUNCATED AT 250 WORDS)

Gonadotropin secretion in azotemic male rats--effect of opioid blockade

The role of endogenous opioids in the control of gonadotropin secretion in uremic male rats was investigated using the narcotic antagonist, naloxone. In order to eliminate the effect of weight loss due to uremia-induced anorexia as a cause of previously described altered gonadotropin secretion in uremia, we also studied a group of normal pair-fed control animals who exhibited a weight loss comparable to that of the uremic animals. Naloxone administration had no effect on the basal or LRH-stimulated peak concentrations of LH and FSH in the normal or the uremic rats. Basal and LRH-stimulated gonadotropin responses in the pair-fed rats were comparable to those seen in the normal rats. Similarly, opioid blockade produced no change in the basal or LRH-stimulated gonadotropin responses in the pair-fed animals. Testosterone concentrations were significantly lower in the uremic and pair-fed animals compared to the normal rats. The data suggest that experimental renal failure is not associated with altered opioidergic tone, as it relates to gonadotropin secretion, or to diminished sensitivity of the gonadotroph to LRH stimulation. The decreased testosterone concentration seen in the uremic and pair-fed rats may reflect abnormalities in gonadal hormone secretion due to primary pathology occurring at the level of the gonad. These abnormalities may be reflected as diminished Leydig cell sensitivity to LH. The inappropriately low concentrations of LH in the presence of low testosterone together with normal gonadotropin response to exogenous LRH also suggest an abnormal secretion of endogenous LRH. It is not clear whether this presumed abnormality in LRH secretion is a primary event or is related to decreased testosterone production by the testes in the uremic and pair-fed rats.