Sequence analysis of mutations and translocations across breast cancer subtypes

Breast carcinoma is the leading cause of cancer-related mortality in women worldwide, with an estimated 1.38 million new cases and 458,000 deaths in 2008 alone. This malignancy represents a heterogeneous group of tumours with characteristic molecular features, prognosis and responses to available therapy. Recurrent somatic alterations in breast cancer have been described, including mutations and copy number alterations, notably ERBB2 amplifications, the first successful therapy target defined by a genomic aberration. Previous DNA sequencing studies of breast cancer genomes have revealed additional candidate mutations and gene rearrangements. Here we report the whole-exome sequences of DNA from 103 human breast cancers of diverse subtypes from patients in Mexico and Vietnam compared to matched-normal DNA, together with whole-genome sequences of 22 breast cancer/normal pairs. Beyond confirming recurrent somatic mutations in PIK3CA, TP53, AKT1, GATA3 and MAP3K1, we discovered recurrent mutations in the CBFB transcription factor gene and deletions of its partner RUNX1. Furthermore, we have identified a recurrent MAGI3-AKT3 fusion enriched in triple-negative breast cancer lacking oestrogen and progesterone receptors and ERBB2 expression. The MAGI3-AKT3 fusion leads to constitutive activation of AKT kinase, which is abolished by treatment with an ATP-competitive AKT small-molecule inhibitor.

Landscape of genomic alterations in cervical carcinomas

Cervical cancer is responsible for 10-15% of cancer-related deaths in women worldwide. The aetiological role of infection with high-risk human papilloma viruses (HPVs) in cervical carcinomas is well established. Previous studies have also implicated somatic mutations in PIK3CA, PTEN, TP53, STK11 and KRAS as well as several copy-number alterations in the pathogenesis of cervical carcinomas. Here we report whole-exome sequencing analysis of 115 cervical carcinoma-normal paired samples, transcriptome sequencing of 79 cases and whole-genome sequencing of 14 tumour-normal pairs. Previously unknown somatic mutations in 79 primary squamous cell carcinomas include recurrent E322K substitutions in the MAPK1 gene (8%), inactivating mutations in the HLA-B gene (9%), and mutations in EP300 (16%), FBXW7 (15%), NFE2L2 (4%), TP53 (5%) and ERBB2 (6%). We also observe somatic ELF3 (13%) and CBFB (8%) mutations in 24 adenocarcinomas. Squamous cell carcinomas have higher frequencies of somatic nucleotide substitutions occurring at cytosines preceded by thymines (Tp*C sites) than adenocarcinomas. Gene expression levels at HPV integration sites were statistically significantly higher in tumours with HPV integration compared with expression of the same genes in tumours without viral integration at the same site. These data demonstrate several recurrent genomic alterations in cervical carcinomas that suggest new strategies to combat this disease.

Oocyte generation in adult mammalian ovaries by putative germ cells in bone marrow and peripheral blood

It has been suggested that germline stem cells maintain oogenesis in postnatal mouse ovaries. Here we show that adult mouse ovaries rapidly generate hundreds of oocytes, despite a small premeiotic germ cell pool. In considering the possibility of an extragonadal source of germ cells, we show expression of germline markers in bone marrow (BM). Further, BM transplantation restores oocyte production in wild-type mice sterilized by chemotherapy, as well as in ataxia telangiectasia-mutated gene-deficient mice, which are otherwise incapable of making oocytes. Donor-derived oocytes are also observed in female mice following peripheral blood transplantation. Although the fertilizability and developmental competency of the BM and peripheral blood-derived oocytes remain to be established, their morphology, enclosure within follicles, and expression of germ-cell- and oocyte-specific markers collectively support that these cells are bona fide oocytes. These results identify BM as a potential source of germ cells that could sustain oocyte production in adulthood.

Recurrent and functional regulatory mutations in breast cancer

Genomic analysis of tumours has led to the identification of hundreds of cancer genes on the basis of the presence of mutations in protein-coding regions. By contrast, much less is known about cancer-causing mutations in non-coding regions. Here we perform deep sequencing in 360 primary breast cancers and develop computational methods to identify significantly mutated promoters. Clear signals are found in the promoters of three genes. FOXA1, a known driver of hormone-receptor positive breast cancer, harbours a mutational hotspot in its promoter leading to overexpression through increased E2F binding. RMRP and NEAT1, two non-coding RNA genes, carry mutations that affect protein binding to their promoters and alter expression levels. Our study shows that promoter regions harbour recurrent mutations in cancer with functional consequences and that the mutations occur at similar frequencies as in coding regions. Power analyses indicate that more such regions remain to be discovered through deep sequencing of adequately sized cohorts of patients.

Exome sequencing of 20,791 cases of type 2 diabetes and 24,440 controls

Protein-coding genetic variants that strongly affect disease risk can yield relevant clues to disease pathogenesis. Here we report exome-sequencing analyses of 20,791 individuals with type 2 diabetes (T2D) and 24,440 non-diabetic control participants from 5 ancestries. We identify gene-level associations of rare variants (with minor allele frequencies of less than 0.5%) in 4 genes at exome-wide significance, including a series of more than 30 SLC30A8 alleles that conveys protection against T2D, and in 12 gene sets, including those corresponding to T2D drug targets (P = 6.1 × 10-3) and candidate genes from knockout mice (P = 5.2 × 10-3). Within our study, the strongest T2D gene-level signals for rare variants explain at most 25% of the heritability of the strongest common single-variant signals, and the gene-level effect sizes of the rare variants that we observed in established T2D drug targets will require 75,000-185,000 sequenced cases to achieve exome-wide significance. We propose a method to interpret these modest rare-variant associations and to incorporate these associations into future target or gene prioritization efforts.

Association of a low-frequency variant in HNF1A with type 2 diabetes in a Latino population

IMPORTANCE

Latino populations have one of the highest prevalences of type 2 diabetes worldwide.

OBJECTIVES

To investigate the association between rare protein-coding genetic variants and prevalence of type 2 diabetes in a large Latino population and to explore potential molecular and physiological mechanisms for the observed relationships.

DESIGN, SETTING, AND PARTICIPANTS

Whole-exome sequencing was performed on DNA samples from 3756 Mexican and US Latino individuals (1794 with type 2 diabetes and 1962 without diabetes) recruited from 1993 to 2013. One variant was further tested for allele frequency and association with type 2 diabetes in large multiethnic data sets of 14,276 participants and characterized in experimental assays.

MAIN OUTCOME AND MEASURES

Prevalence of type 2 diabetes. Secondary outcomes included age of onset, body mass index, and effect on protein function.

RESULTS

A single rare missense variant (c.1522G>A [p.E508K]) was associated with type 2 diabetes prevalence (odds ratio [OR], 5.48; 95% CI, 2.83-10.61; P = 4.4 × 10(-7)) in hepatocyte nuclear factor 1-α (HNF1A), the gene responsible for maturity onset diabetes of the young type 3 (MODY3). This variant was observed in 0.36% of participants without type 2 diabetes and 2.1% of participants with it. In multiethnic replication data sets, the p.E508K variant was seen only in Latino patients (n = 1443 with type 2 diabetes and 1673 without it) and was associated with type 2 diabetes (OR, 4.16; 95% CI, 1.75-9.92; P = .0013). In experimental assays, HNF-1A protein encoding the p.E508K mutant demonstrated reduced transactivation activity of its target promoter compared with a wild-type protein. In our data, carriers and noncarriers of the p.E508K mutation with type 2 diabetes had no significant differences in compared clinical characteristics, including age at onset. The mean (SD) age for carriers was 45.3 years (11.2) vs 47.5 years (11.5) for noncarriers (P = .49) and the mean (SD) BMI for carriers was 28.2 (5.5) vs 29.3 (5.3) for noncarriers (P = .19).

CONCLUSIONS AND RELEVANCE

Using whole-exome sequencing, we identified a single low-frequency variant in the MODY3-causing gene HNF1A that is associated with type 2 diabetes in Latino populations and may affect protein function. This finding may have implications for screening and therapeutic modification in this population, but additional studies are required.

Control of lymphocyte development by the Ikaros gene family

Lymphoid cell differentiation relies on precisely orchestrated gene activation and repression events. Gene targeting studies have demonstrated crucial roles for the transcription factors Ikaros and Aiolos in regulating multiple stages of B and T cell development. Recent experiments suggest that Ikaros and Aiolos set B cell antigen-receptor (BCR)- and TCR-mediated signaling thresholds and that the molecules exist within T cells in nuclear complexes that contain nucleosome remodeling and histone deacetylase activities.

Genetic variation in the vulnerable and endemic Monkey Puzzle tree, detected using RAPDs

Araucaria araucana (Monkey Puzzle), a southern South American tree species of exceptional cultural and economic importance, is of conservation concern owing to extensive historical clearance and current human pressures. Random amplified polymorphic DNA (RAPD) markers were used to characterise genetic heterogeneity within and among 13 populations of this species from throughout its natural range. Extensive genetic variability was detected and partitioned by analysis of molecular variance, with the majority of variation existing within populations (87.2%), but significant differentiation was recorded among populations (12.8%). Estimates of Shannon's genetic diversity and percent polymorphism were relatively high for all populations and provide no evidence for a major reduction in genetic diversity from historical events, such as glaciation. All pairwise genetic distance values derived from analysis of molecular variance (Phi(ST)) were significant when individual pairs of populations were compared. Although populations are geographically divided into Chilean Coastal, Chilean Andes and Argentinean regions, this grouping explained only 1.77% of the total variation. Within Andean groups there was evidence of a trend of genetic distance with increasing latitude, and clustering of populations across the Andes, suggesting postglacial migration routes from multiple refugia. Implications of these results for the conservation and use of the genetic resource of this species are discussed.

A novel method for imaging apoptosis using a caspase-1 near-infrared fluorescent probe

Here we describe a novel method for imaging apoptosis in cells using a near-infrared fluorescent (NIRF) probe selective for caspase-1 (interleukin 1beta-converting enzyme, ICE). This biocompatible, optically quenched ICE-NIRF probe incorporates a peptide substrate, which can be selectively cleaved by caspase-1, resulting in the release of fluorescence signal. The specificity of this probe for caspase-1 is supported by various lines of evidence: 1) activation by purified caspase-1, but not another caspase in vitro; 2) activation of the probe by infection of cells with a herpes simplex virus amplicon vector (HGC-ICE-lacZ) expressing a catalytically active caspase-1-lacZ fusion protein; 3) inhibition of HGC-ICE-lacZ vector-induced activation of the probe by coincubation with the caspase-1 inhibitor YVAD-cmk, but not with a caspase-3 inhibitor; and 4) activation of the probe following standard methods of inducing apoptosis with staurosporine, ganciclovir, or ionizing radiation in culture. These results indicate that this novel ICE-NIRF probe can be used in monitoring endogenous and vector-expressed caspase-1 activity in cells. Furthermore, tumor implant experiments indicate that this ICE-NIRF probe can be used to detect caspase-1 activity in living animals. This novel ICE-NIRF probe should prove useful in monitoring endogenous and vector-expressed caspase-1 activity, and potentially apoptosis in cell culture and in vivo.

Passive and active immunity in infants born to mothers with SARS-CoV-2 infection during pregnancy: prospective cohort study

OBJECTIVE

To investigate maternal immunoglobulins' (IgM, IgG) response to SARS-CoV-2 infection during pregnancy and IgG transplacental transfer, to characterise neonatal antibody response to SARS-CoV-2 infection, and to longitudinally follow actively and passively acquired antibodies in infants.

DESIGN

A prospective observational study.

SETTING

Public healthcare system in Santa Clara County (California, USA).

PARTICIPANTS

Women with symptomatic or asymptomatic SARS-CoV-2 infection during pregnancy and their infants were enrolled between 15 April 2020 and 31 March 2021.

OUTCOMES

SARS-CoV-2 serology analyses in the cord and maternal blood at delivery and longitudinally in infant blood between birth and 28 weeks of life.

RESULTS

Of 145 mothers who tested positive for SARS-CoV-2 during pregnancy, 86 had symptomatic infections: 78 with mild-moderate symptoms, and 8 with severe-critical symptoms. The seropositivity rates of the mothers at delivery was 65% (95% CI 0.56% to 0.73%) and the cord blood was 58% (95% CI 0.49% to 0.66%). IgG levels significantly correlated between the maternal and cord blood (Rs=0.93, p<0.0001). IgG transplacental transfer ratio was significantly higher when the first maternal positive PCR was 60-180 days before delivery compared with <60 days (1.2 vs 0.6, p<0.0001). Infant IgG seroreversion rates over follow-up periods of 1-4, 5-12, and 13-28 weeks were 8% (4 of 48), 12% (3 of 25), and 38% (5 of 13), respectively. The IgG seropositivity in the infants was positively related to IgG levels in the cord blood and persisted up to 6 months of age. Two newborns showed seroconversion at 2 weeks of age with high levels of IgM and IgG, including one premature infant with confirmed intrapartum infection.

CONCLUSIONS

Maternal SARS-CoV-2 IgG is efficiently transferred across the placenta when infections occur more than 2 months before delivery. Maternally derived passive immunity may persist in infants up to 6 months of life. Neonates are capable of mounting a strong antibody response to perinatal SARS-CoV-2 infection.

ETS-core binding factor: a common composite motif in antigen receptor gene enhancers

A tripartite domain of the murine immunoglobulin mu heavy-chain enhancer contains the muA and muB elements that bind ETS proteins and the muE3 element that binds leucine zipper-containing basic helix-loop-helix (bHLH-zip) factors. Analysis of the corresponding region of the human mu enhancer revealed high conservation of the muA and muB motifs but a striking absence of the muE3 element. Instead of bHLH-zip proteins, we found that the human enhancer bound core binding factor (CBF) between the muA and mu elements; CBF binding was shown to be a common feature of both murine and human enhancers. Furthermore, mutant enhancers that bound prototypic bHLH-zip proteins but not CBF did not activate transcription in B cells, and conversely, CBF transactivated the murine enhancer in nonlymphoid cells. Taking these data together with the earlier analysis of T-cell-specific enhancers, we propose that ETS-CBF is a common composite element in the regulation of antigen receptor genes. In addition, these studies identify the first B-cell target of CBF, a protein that has been implicated in the development of childhood pre-B-cell leukemias.

Systematic review and meta-analysis of randomised clinical trials on topical treatments for vernal keratoconjunctivitis

AIMS

The aim of this study was to assess the efficacy of currently available topical drugs for vernal keratoconjunctivitis (VKC) through a meta-analysis of randomised clinical trials (RCTs).

METHODS

Twenty-seven RCTs (n = 2184 eyes) that had evaluated the efficacy of topical drugs for the treatment of VKC were selected according to the set criteria; 10 of these trials were suitable for statistical analysis and were enrolled in the meta-analysis. Articles published up to December 2005 were identified from the following

DATA SOURCES

Medline, Embase, Lilacs, the Cochrane Controlled Trials Register, and references from relevant articles. Articles in any language published with an English abstract, were screened, and those selected for inclusion were written in English, French, German, Italian, Portuguese or Spanish. The quality of the trials was assessed by the Delphi list. Statistical analysis was performed using STATA software.

RESULTS

A significant improvement in all signs and symptoms, except photophobia, was observed after topical treatment for active VKC, independent of the type of treatment. Comparison of the efficacy of different drugs was not possible due to a lack of standardised criteria among studies.

CONCLUSION

The currently available topical drugs are effective in treating acute phases of VKC. However, there is a lack of evidence to support the recommendation of one specific type of medication for treating this disorder. There is a need for standard criteria to assess diagnosis and therapy based on severity. There is also a need for RCTs assessing long-term effects of single drugs to control the disease and to prevent complications.

A Loss-of-Function Splice Acceptor Variant in IGF2 Is Protective for Type 2 Diabetes

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage-dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction.

LMO4 can interact with Smad proteins and modulate transforming growth factor-beta signaling in epithelial cells

LIM-only protein 4 (LMO4) plays critical roles in mammalian development, and has been proposed to play roles in epithelial oncogenesis, including breast cancer. As LMO4 is highly expressed in the epithelial compartments at locations of active mesenchymal-epithelial interactions, we reasoned that LMO4 might act by modulating signaling pathways involved in mesenchymal-epithelial signaling. One such candidate signal is the transforming growth factor-beta (TGFbeta) cytokine pathway, which plays important roles both in development and cancer. We show here that the transcriptional response to TGFbeta in epithelial cells is sensitive to LMO4 levels; both up- and downregulation of LMO4 can enhance TGFbeta signaling as assessed by a TGFbeta-responsive reporter gene. Furthermore, LMO4 can interact with the MH1 and linker domains of receptor-mediated Smad proteins, and associate with the endogenous TGFbeta-responsive Plasminogen Activator Inhibitor-1 gene promoter in a TGFbeta-dependent manner, suggesting that such interactions may mediate the effects of LMO4 on TGFbeta signaling. When introduced into mammary epithelial cells, LMO4 potentiated the growth-inhibitory effects of TGFbeta in those cells. These results define a new function for LMO4 as a coactivator in TGFbeta signaling, and provide a potential novel mechanism for LMO4-mediated regulation in development and oncogenesis.

SILK flow diverter for complex intracranial aneurysms: a Canadian registry

INTRODUCTION

The SILK flow diverter (SFD) is used for the treatment of complex intracranial aneurysms. Small case series have been reported in the literature but few studies with a large number of patients have been published. We present our experience with the SFD for the treatment of intracranial aneurysms in Canada.

METHODS

Centers across Canada using SFDs were contacted to fill out a case report form for patients treated with an SFD in their center. Individual centers were responsible for approval from their ethics committee. Image analysis was performed by individual operators. The case report forms were collected and the final analysis was performed.

RESULTS

A total of 92 patients were treated with SFDs in eight centers in Canada between January 2009 and August 2013. The aneurysms were located in the posterior circulation in 16 patients and in the anterior circulation in 76 patients. Most aneurysms (75%) were saccular in shape; 22% were fusiform and 3% were blister aneurysms. The size of the aneurysms varied from 2 to 60 mm with the neck varying from 2 to 60 mm. Perioperative morbidity and mortality were 8.7% and 2.2%, respectively. At the last available follow-up, 83.1% of the aneurysms were either completely or near-completely occluded. The rate of complications was higher for fusiform aneurysms (p<0.001).

CONCLUSIONS

The SFD appears to be an important tool for the treatment of complex intracranial aneurysms. Treatment outcomes and complication rates remain a problem, but should be considered in the context of available alternative interventions. Ongoing analysis of flow-diverting stents for radiographic and clinical performance is required.

Bone marrow transplantation restores immune system function and prevents lymphoma in Atm-deficient mice

Ataxia-telangiectasia (A-T) is a human autosomal recessive disease caused by mutations in the gene encoding ataxia-telangiectasia mutated (ATM). A-T is characterized by progressive cerebellar degeneration, variable immunodeficiency, and a high incidence of leukemia and lymphoma. Recurrent sino-pulmonary infections secondary to immunodeficiency and hematopoietic malignancies are major causes of morbidity and mortality in A-T patients. In mice, an introduced mutation in Atm leads to a phenotype that recapitulates many of the symptoms of A-T, including immune system abnormalities and susceptibility to malignancy. Here we show that the replacement of the bone marrow compartment in Atm knockout mice (Atm-/-) using a clinically relevant, nonmyeloablative host-conditioning regimen can be used to overcome the immune deficiencies and prevent the malignancies observed in these mice. Therefore, bone marrow transplantation may prove to be of therapeutic benefit in A-T patients. (Blood. 2004;104:572-578)

Combinatorial determinants of tissue-specific transcription in B cells and macrophages

A tripartite domain of the immunoglobulin mu heavy-chain gene enhancer that activates transcription in B cells contains binding sites for PU.1, Ets-1, and a leucine zipper-containing basic helix-loop-helix factor. Because PU.1 is expressed only in B cells and macrophages, we tested the activity of a minimal mu enhancer fragment in macrophages by transient transfections. The minimal mu enhancer activated transcription in macrophages, and the activity was dependent on all three sites. Analysis of mutated enhancers, in which spacing and orientation of the ETS protein binding sites had been changed, suggested that the mechanisms of enhancer activation were different in B cells and macrophages. Thus, ETS protein binding sites may be combined in different ways to generate tissue-specific transcription activators. Despite the activity of the minimal enhancer in macrophages, a larger mu enhancer fragment was inactive in these cells. We propose that formation of the nucleoprotein complex that is formed on the minimal enhancer in macrophages cannot be helped by the neighboring muE elements that are essential for activity of the monomeric enhancer.

Healthcare-seeking patterns among immigrants in Portugal

Equity of access to health services is a major concern as it is an important precondition for positive health outcomes. However, inequities in use of health services among immigrant populations persist. Despite the increasing research in the field, patterns of healthcare seeking among immigrant populations and its associated factors are not fully understood. This study aimed to investigate healthcare-seeking patterns among immigrants in Portugal and identify factors associated with utilisation of health services. A cross-sectional study was conducted between October 2008 and May 2009 with a sample of 1,375 immigrants residing in the Lisbon region. Data were collected through a structured questionnaire applied by trained interviewers. Two stepwise logistic regressions were conducted to identify which factors were associated with utilisation of the National Health Service (NHS) and with healthcare seeking for the first time in Portugal at the Primary Health Care service, estimated by calculating odds ratios and 95% confidence intervals. Among participants, around 77% reported having used the NHS; 50% sought health-care for the first time at the Primary Health Care service and 33% at the emergency room. Lower odds of having used the NHS were associated with being male, Brazilian or eastern European compared with being African, and undocumented. Lower odds of having sought health-care for the first time at the Primary Health Care service were associated with being male and undocumented. These results suggest that further efforts are needed to tackle inequalities in access to care and promote the utilisation of health services, particularly among the more vulnerable immigrant groups. Increasing appropriate utilisation of health services, including the primary and preventive care services, may lead to better health outcomes. Immigrants' involvement and participation should be incorporated into the development of health strategies to improve access and utilisation of healthcare services.

Upregulation of ICAM-1 expression in the conjunctiva of patients with chronic graft-versus-host disease

PURPOSE

To correlate conjunctival intercellular adhesion molecule 1 (ICAM-1) expression with cytologic and clinical findings of chronic graft-versus-host disease (GVHD).

METHODS

Seven patients with chronic GVHD-related keratoconjunctivitis and five age-matched normal controls were recruited for the study. Clinical examination included medical history, visual acuity, evaluation of ocular signs and symptoms (scored from 0 to 3), corneal fluorescein staining (scored from 0 to 5 on the basis of the number of corneal sectors involved), Schirmer test type I, and break-up time (BUT). Impression cytology samples were collected from the nasal and inferior bulbar conjunctiva of patients and controls. Goblet cells were counted in three randomly selected fields and averaged. Immunofluorescent staining for ICAM-1 was carried out and the percentage of cells expressing the marker was evaluated.

RESULTS

All patients showed signs and symptoms of keratoconjunctivitis sicca. Schirmer test type I and BUT were reduced (4.8+/-6.7 mm/5 min and 3.9+/-2.7 seconds, respectively). Goblet cells were significantly reduced in GVHD eyes with respect to normal eyes (65+/-30.5 and 192+/-16.9 cells/field respectively; p<0.001). Goblet cell number was directly related to Schirmer test values (p<0.01, rho=0.817) and inversely related to total sign score (p<0.01, rho=-0.939). ICAM-1 expression was increased in GVHD eyes with respect to normal controls, in which no staining was observed. ICAM-1 expression showed an inverse relation to goblet cell number (p<0.01, rho=-0.852) and Schirmer test values (p<0.01, rho=-0.926), and was directly correlated to total sign score (p<0.01, rho=0.982).

CONCLUSIONS

Conjunctival ICAM-1 expression is increased in GVHD patients. The severity of the disease is associated with tear parameters, goblet cell decrease, and inflammatory markers, such as ICAM-1.

Results of a pilot study of the time to azoospermia after vasectomy in Mexico City

In a joint pilot study by Family Health International (FHI), AVSC International, and the Instituto Mexicano del Seguro Social (IMSS), information was gathered on the determinants of azoospermia following vasectomy on 38 healthy men who chose vasectomy for contraception. The time and number of ejaculations associated with loss of sperm motility and loss of sperm eosin vital staining were also evaluated. "Azoospermia" was defined on the basis of two consecutive azoospermic semen samples collected at least 3 days apart. The single decrement life table method was used to calculate weekly gross cumulative life table rates for the time to azoospermia, zero motility, and zero viability. The Kaplan-Meier method was used to calculate the product-limit estimates of the cumulative rates for the total number of ejaculations to azoospermia, 0% motility and 0% viability. The median time to azoospermia was 10 weeks and at the end of week 20, the life table rate (+/- standard error) was 93.0 (+/- 6.30) weeks/100 men. The median number of ejaculations to azoospermia was between 25 and 30, and the cumulative rate (+/- standard error) at 60 ejaculations reached 94.5 (+/- 5.16)/100 men.

Orbital Reconstruction After Eyelid- and Conjunctiva-Sparing Orbital Exenteration

PURPOSE

To describe the technique and results of eyelid- and conjunctiva-sparing orbital exenteration with temporalis transfer and dermis-fat graft.

METHODS

Five patients who underwent this procedure were studied, based on retrospective chart review. Schematic drawings were produced to illustrate the surgical technique.

RESULTS

The study included three female and two male patients with an age range of 7 to 76 years. Two patients required surgery for invasive optic nerve sheath meningioma, one for hemangiopericytoma, and the fourth for mesenchymal chondrosarcoma. The last patient had eyelid-sparing exenteration performed more than 20 years earlier for retinoblastoma and underwent a similar reconstruction. One case was complicated by infection and graft atrophy. The remaining four cases retained orbital volume and eyelid structures with a reasonable cosmetic outcome. Average follow-up period was 21 months, during which one patient had development of intracranial meningioma at the proximal end of the optic canal.

CONCLUSIONS

Eyelid- and conjunctiva-sparing orbital exenteration with temporalis transfer and dermis-fat graft is a useful technique that minimizes the usual deformity and achieves good results. Case selection is emphasized, as this technique is mainly reserved for histopathologically benign orbital lesions that exhibit local aggressive behavior and for malignant lesions only if there is no eyelid, lacrimal gland, or orbital fissure involvement nor significant conjunctival or deep extension of an intraocular tumor.

Human hepatocyte transplantation in patients with hepatic failure awaiting a graft

BACKGROUND

Hepatocyte transplantation (HT) has the potential to become a promising treatment to temporarily support liver function in patients with liver failure.

METHODS

Two patients, who had already received a liver transplant (LT) in the past, with an end-stage liver disease due to recurrent hepatitis C virus cirrhosis, suffering acute-on-chronic liver failure while on the waiting list for an LT, received HT as a bridge to whole-organ retransplantation. After HT and during intensive care unit admission, blood tests and ammonia levels were determined every 12 and 24 h, respectively, before and after each hepatocyte infusion.

RESULTS

The present study describes monitoring of analytical and clinical parameters and improvement of liver function following HT. In both patients, we managed to lower the blood ammonia levels and clinically improve the degree of hepatic encephalopathy, thus serving as a bridge to liver retransplantation in 1 patient.

CONCLUSIONS

We believe that this therapy may be an alternative treatment in patients with chronic liver disease who suffer episodes of acute decompensation as a bridge to conventional LT.