Function Is More Reliable than Quantity to Follow Up the Humoral Response to the Receptor-Binding Domain of SARS-CoV-2-Spike Protein after Natural Infection or COVID-19 Vaccination.

Both the SARS-CoV-2 pandemic and emergence of variants of concern have highlighted the need for functional antibody assays to monitor the humoral response over time. Antibodies directed against the spike (S) protein of SARS-CoV-2 are an important component of the neutralizing antibody response. In this work, we report that in a subset of patients-despite a decline in total S-specific antibodies-neutralizing antibody titers remain at a similar level for an average of 98 days in longitudinal sampling of a cohort of 59 Hispanic/Latino patients exposed to SARS-CoV-2. Our data suggest that 100% of seroconverting patients make detectable neutralizing antibody responses which can be quantified by a surrogate viral neutralization test. Examination of sera from ten out of the 59 subjects which received mRNA-based vaccination revealed that both IgG titers and neutralizing activity of sera were higher after vaccination compared to a cohort of 21 SARS-CoV-2 naïve subjects. One dose was sufficient for the induction of a neutralizing antibody, but two doses were necessary to reach 100% surrogate virus neutralization in subjects irrespective of previous SARS-CoV-2 natural infection status. Like the pattern observed after natural infection, the total anti-S antibodies titers declined after the second vaccine dose; however, neutralizing activity remained relatively constant for more than 80 days after the first vaccine dose. Furthermore, our data indicates that-compared with mRNA vaccination-natural infection induces a more robust humoral immune response in unexposed subjects. This work is an important contribution to understanding the natural immune response to the novel coronavirus in a population severely impacted by SARS-CoV-2. Furthermore, by comparing the dynamics of the immune response after the natural infection vs. the vaccination, these findings suggest that functional neutralizing antibody tests are more relevant indicators than the presence or absence of binding antibodies.

Function is more reliable than quantity to follow up the humoral response to the Receptor Binding Domain of SARS- CoV-2 Spike protein after natural infection or COVID-19 vaccination.

Both the SARS-CoV-2 pandemic and emergence of variants of concern have highlighted the need for functional antibody assays to monitor the humoral response over time. Antibodies directed against the spike (S) protein of SARS-CoV-2 are an important component of the neutralizing antibody response. In this work, we report that in a subset of patients-despite a decline in total S-specific antibodies-neutralizing antibody titers remain at a similar level for an average of 98 days in longitudinal sampling of a cohort of 59 Hispanic/Latino patients exposed to SARS-CoV-2. We also report that serum neutralization capacity correlates with IgG titers, wherein IgG1 was the predominant isotype (62.71%), followed by IgG4 (15.25%), IgG3 (13.56%), and IgG2 (8.47%) at the earliest tested timepoint. IgA titers were detectable in just 28.81% of subjects, and only 62.71% of subjects had detectable IgM in the first sample despite confirmation of infection by a molecular diagnostic assay. Our data suggests that 100% of seroconverting patients make detectable neutralizing antibody responses which can be quantified by a surrogate viral neutralization test. Examination of sera from 10 out of the 59 subjects which had received an initial first dose of mRNA-based vaccination revealed that both IgG titers and neutralizing activity of sera were higher after vaccination compared to a cohort of 21 SARS-CoV-2 naïve subjects. One dose was sufficient for induction of neutralizing antibody, but two doses were necessary to reach 100% surrogate virus neutralization in subjects irrespective of previous SARS-CoV-2 natural infection status. Like the pattern seen after natural infection, after the second vaccine dose, the total anti-S antibodies titers declined, however, neutralizing activity remained relatively constant for more than 80 days after the first vaccine dose. The decline in anti-S antibody titer, however, was significantly less in pre-exposed individuals, highlighting the potential for natural infection to prime a more robust immune response to the vaccine. Furthermore, our data indicates that-compared with mRNA vaccination-natural infection induces a more robust humoral immune response in unexposed subjects. However, this difference was significant only when neutralizing antibody titers were compared among the two groups. No differences were observed between naturally infected and vaccinated individuals when total anti-S antibodies and IgG titers were measured. This work is an important contribution to understanding the natural immune response to the novel coronavirus in a population severely impacted by SARS-CoV-2. Furthermore, by comparing the dynamics of the immune response after the natural infection vs. the vaccination, these findings suggest that a functional neutralizing antibody tests are more relevant indicators than the presence or absence of binding antibodies. In this context, our results also support standardizing methods of assessing the humoral response to SARS-CoV-2 when determining vaccine efficacy and describing the immune correlates of protection for SARS-CoV-2.

Breast Cancer in a Caribbean Population in Transition: Design and Implementation of the Atabey Population-Based Case-Control Study of Women in the San Juan Metropolitan Area in Puerto Rico.

Global breast cancer incidence varies considerably, particularly in comparisons of low- and high-income countries; rates may vary even within regions. Breast cancer rates for Caribbean countries are generally lower than for North America and Europe. Rates in Puerto Rico are in the middle of the range between the highest and the lowest Caribbean countries. Populations in transition, with greater variability in risk factor exposures, provide an important opportunity to better understand breast cancer etiology and as potential sources of variation in rates. Understanding of exposures across the life span can potentially contribute to understanding regional differences in rates. We describe here the design and implementation of a population-based, case-control study in the San Juan Metropolitan Area (SJMA) of Puerto Rico, the Atabey Epidemiology of Breast Cancer Study. We describe steps taken to ensure that the study was culturally appropriate, leveraging the Atabey researchers' understanding of the culture, local health system, and other required resources to effectively recruit participants. A standardized, in-person interview was developed, with attention to life course events customized to the study population. In order to understand variation in global breast cancer rates, studies customized to the populations outside of North America and Europe are required.

Mitochondrial DNA Integrity Is Maintained by APE1 in Carcinogen-Induced Colorectal Cancer.

Changes in mitochondrial DNA (mtDNA) integrity have been reported in many cancers; however, the contribution of mtDNA integrity to tumorigenesis is not well understood. We used a transgenic mouse model that is haploinsufficient for the apurinic/apyrimidinic endonuclease 1 (Apex1+/-) gene, which encodes the base excision repair (BER) enzyme APE1, to determine its role in protecting mtDNA from the effects of azoxymethane (AOM), a carcinogen used to induce colorectal cancer. Repair kinetics of AOM-induced mtDNA damage was evaluated using qPCR after a single AOM dose and a significant induction in mtDNA lesions in colonic crypts from both wild-type (WT) and Apex1+/-animals were observed. However, Apex1+/- mice had slower repair kinetics in addition to decreased mtDNA abundance. Tumors were also induced using multiple AOM doses, and both WT and Apex1+/-animals exhibited significant loss in mtDNA abundance. Surprisingly, no major differences in mtDNA lesions were observed in tumors from WT and Apex1+/- animals, whereas a significant increase in nuclear DNA lesions was detected in tumors from Apex1+/- mice. Finally, tumors from Apex1+/- mice displayed an increased proliferative index and histologic abnormalities. Taken together, these results demonstrate that APE1 is important for preventing changes in mtDNA integrity during AOM-induced colorectal cancer.Implications: AOM, a colorectal cancer carcinogen, generates damage to the mitochondrial genome, and the BER enzyme APE1 is required to maintain its integrity. Mol Cancer Res; 15(7); 831-41. ©2017 AACR.

Expression of Basal-like Biomarkers in Triple Negative Invasive Breast Carcinoma in Puerto Rico.

OBJECTIVE: Routine Progesterone and Estrogen hormone receptor proteins and human epidermal growth factor receptor 2 (HER-2) analysis on invasive breast carcinomas provide therapeutic and prognostic values, revealing significant subgroups: luminal A, luminal B, HER-2 and the "triple negative" tumors. The aim of this study was to determine the expression of basal cytokeratins and Epidermal Growth Factor Receptor in "triple negative" invasive breast carcinomas in Puerto Rico women. METHODS: All invasive breast carcinoma cases received from 2008 to 2010 were included. Assessment of tumoral expression of Estrogen Receptor, Progesterone Receptor and HER-2 was performed. The cases were divided into groups based on their molecular categories and analyzed according to the age. "Triple negative" tumors were further analyzed according to their expression of Epidermal Growth Factor Receptor and cytokeratins 5/6 and 14. RESULTS: From 717 cases reviewed, 487 cases of invasive breast carcinoma were included. The molecular categories were 66%, 10%, 9% and 15% for the luminal A, luminal B, Her-2 and "triple negative" groups, respectively. No significant difference (p= 0.64) was observed between the molecular categories and the age of the patients. Assessment of basal cytokeratins and Epidermal Growth Factor Receptor expression was performed on 41 "triple negative" tumors; 71% expressed at least one basal cytokeratin or Epidermal Growth Factor Receptor and 29% were negative to all markers. CONCLUSION: Prevalence and relation between the molecular categories and the expression of basal cytokeratins in "triple negative" tumors in our population is comparable to other published data.

Prosthetic joint infections due to Staphylococcus aureus and coagulase-negative staphylococci.

PURPOSES: To evaluate the specific characteristics, outcome, and predictors of failure of prosthetic joint infections (PJI) due to S. aureus and coagulase-negative staphylococci (CNS) treated with open debridement and retention of the implant. METHODS: PJI due to S. aureus or CNS prospectively registered in a database from 1999 to 2009 were retrospectively reviewed. During the study period, 106 patients met the inclusion criteria. The mean follow-up period was 3.8 years and for at least 2 years in all patients. The failure rate was 23.6% (25 out of 106). The only variable significantly associated with failure in the global cohort was polymicrobial infection (38.7% vs. 17.3%, p = 0.024). Fifty-seven (53.8%) patients had an infection due to S. aureus and 49 (46.2%) due to CNS. Among S. aureus infections, 95% corresponded to primary arthroplasties while 98% of PJIs due to CNS were after revision arthroplasties (p<0.001). C-reactive protein was significantly higher in PJI due to S. aureus (9.5 mg/dl vs. 4.9 mg/dl, p = 0.007). The rate of methicillin-resistance (8.8% vs. 59.2%, p<0.001) and fluoroquinolone-resistance (15.8% vs. 34.7%, p = 0.005) was significantly higher in CNS infections. The global failure rate was higher in S. aureus infections (28% vs. 18.3. p = 0.26). In S. aureus infections, patients diagnosed within the first 15 days after joint arthroplasty (p = 0.031) and with bacteremia (p = 0.046) had poor pro-gnosis. In CNS infections only the location of the prosthesis (knee 27.6% vs. hip 5%, p = 0.045) was associated with failure. CONCLUSIONS: PJIs due to S. aureus were mainly in primary arthroplasties; they had a higher inflammatory response; and the strains were more susceptible to fluoroquinolones and methicillin than CNS infections. S. aureus infections had a higher failure rate than CNS infections, however, the difference was not statistically significant. There were few factors associated with failure and they were different in S. aureus and CNS infections.

Decreased serum linezolid concentrations in two patients receiving linezolid and rifampicin due to bone infections.

Methicillin-resistant Staphylococcus is a common cause of orthopaedic implant infections. In such cases, rifampicin is the antibiotic of choice, but it should not be administered alone to avoid the selection of resistant mutants. Linezolid has activity against resistant staphylococci and a high oral bioavailability; therefore, it could be a good option for combining with rifampicin. We describe 2 patients admitted to our hospital due to orthopaedic implant infections, who received combination therapy with linezolid and rifampicin. In both cases, the trough serum concentration of linezolid during rifampicin treatment was below the minimum inhibitory concentration required to inhibit the growth of 90% of organisms (MIC(90)) for staphylococci, but increased after rifampicin withdrawal. This finding suggests an interaction between rifampicin and linezolid, and a possible explanation is discussed.

Prevalence of spondyloarthropathy in Puerto Rican patients with inflammatory bowel disease.

INTRODUCTION: Inflammatory arthritis is the most common extraintestinal manifestation in patients with inflammatory bowel disease (IBD). Approximately 20% of all IBD patients will present with peripheral arthritis, sacroiliitis, or spondylitis. The purpose of this study was to determine the prevalence of spondyloarthropathy and sacroiliitis in Puerto Rican patients with IBD. METHODS: Patients were obtained from the IBD specialty clinic and all had a diagnosis of ulcerative colitis or Crohn's disease. All the patients who agreed to participate were entered in the study. Patients completed a questionnaire and underwent a physical examination. Radiologic examination of the lumbosacral spine and sacroiliac joints was performed. Blood samples were obtained for determining human leukocyte antigen class I and were serologically analyzed in the pathology department laboratory. Data were analyzed by using SPSS 10.0 for Windows. RESULTS: One hundred patients were enrolled; 57% had ulcerative colitis, and 43% had Crohn's disease. Fifty percent were female, and the mean age was 37 years (standard deviation 14.96 years). Seventy-seven percent reported history of joint pain, and 47% reported limitation due to joint pain. Physical examination revealed peripheral synovitis in five patients and spinal tenderness in 46 patients. Of the 100 patients, 42 had inflammatory back pain and fulfilled the criteria for spondyloarthropathy. Radiographs were obtained in 76 patients. They revealed grade 2 or greater sacroiliitis in 10 patients (13%) and ankylosing spondylitis in two patients (2.6%). Of the 82 patients with blood samples, human leukocyte antigen B27 was found in five patients (6%). CONCLUSIONS: Of the study population of Puerto Ricans with IBD, 42% had spondyloarthropathy. This prevalence is higher than reported in Caucasians (20%-30%). Sacroiliitis had a similar prevalence as reported in Caucasians, but the prevalence of peripheral arthritis was much lower.

Major histocompatibility complex class II polymorphisms and risk of cervical cancer in Puerto Rican women.

Association between HLA antigens and cervical squamous cell carcinoma has been described in several populations. To verify whether HLA-DRB1 and DQB1 diversity is related to cervical cancer in Puerto Rican women, 40 cases and 50 controls were HLA typed. DRB1*16 (POR=2.89) and DRB1*11 (POR=1.74) were positively associated with cervical cancer. A negative association was found with DRB1*01 (POR=0.52), DRB1*04 (POR=0.60), DRB1*14 (POR=0.33), DRB1*15 (POR=0.65), DQB1*04 (POR=0.33), DQB1*05 (POR=0.64) and DQB1*06 (POR=0.65). We suggest that HLA Class H polymorphisms are involved in genetic susceptibility to cervical cancer in Puerto Rican women. These results should be confirmed in studies with larger sample size to preclude the possibility of false positive observations.

Evidence for mutational cis-acting factors affecting mutagenesis in the ornithine transcarbamylase gene.

Ornithine transcarbamylase (OTC; EC 2.1.3.3) is an urea cycle enzyme coded by a gene located at Xp21.1. The genetic deficiency is caused by a wide spectrum of pathological mutations, most of them occurring de novo. Using two (CA)n flanking markers of the OTC gene (DXS997 and DXS1068), we have defined the haplotypic background underlying 37 different mutational events and compared the results with a random sample of control chromosomes (N=141) from Iberia Peninsula. The allelic distribution of the (CA)n markers revealed significant differences between affected and non-affected chromosomes. One particular haplotypic combination can be considered as a risk factor for carrying OTC mutations, with a relative risk of 13.3 (95% confidence interval 2.89-61.5, p=1.5 x 10(-5)). Since most of pathogenic OTC mutations are short-lived or de novo, these findings strongly support the hypothesis that a specific haplotypic background confers a higher risk for mutation occurrence at this locus.

Comparison of outpatient point of care glucose testing vs venous glucose in the clinical laboratory.

The purpose of this study was to evaluate the accuracy of glucometers in assessing glucose levels in outpatients. The investigation consisted in the analysis of retrospective validation data (obtained at the Clinical Laboratory of the Puerto Rico Medical Services Administration) and the analysis of data obtained from forty outpatients. Glucose concentration was obtained from these outpatient samples using the patients' glucometers and a clinical laboratory analyzer (hexokinase method). Statistical analysis included descriptive and correlation measures and t-test. Results revealed that accurate glucose values were obtained by the glucometers utilized in both the validation process and the outpatients (POCT) procedure. The investigation also demonstrated the need by outpatients to receive proper training in handling their glucometers.

H intragenic polymorphisms and haplotype analysis in the ornithine transcarbamylase (OTC) gene and their relevance for tracking the inheritance of OTC deficiency.

The "private" nature of most mutations causing ornithine transcarbamylase (OTC) deficiency makes mutation identification in the patients difficult. Further, the PCR-amplification technology generally used for the genetic diagnosis of the deficiency misses large deletions in carrier females. Intragenic OTC polymorphisms may allow detection of these deletions and may represent an alternative to mutation detection for prenatal diagnosis and carrier identification in families with a history of inherited OTC deficiency. A new highly informative polymorphism (allele frequencies, 0.66/0.34) in intron 3 of the OTC gene (IVS3-39_40insT) is reported here, and allelic frequencies of 16 additional intragenic OTC polymorphisms are determined in 133-35 (average per polymorphism, 72) unrelated chromosomes. In addition to the novel polymorphism, only three of the studied polymorphisms (Lys46Arg, allelic frequency 0.68/0.32; IVS3-8A>T, 0.34/0.66; Gln270Arg, 0.97/0.03) are confirmed to be informative. These provide, together with another reported polymorphism (IVS4-7A>G; reported allelic frequency 0.71/0.29; Plante and Tuchman, 1998), a set of highly valuable markers of the OTC gene. Nevertheless, the combined informativity of the studied polymorphisms is limited by their distribution in only four haplotypes with one of them predominating (65% of the sampled chromosomes). Although this haplotype composition may be restricted to the Iberian peninsula (the origin of the samples), more informative polymorphisms are required to increase the diagnostic potential and, particularly, to identify large deletions affecting OTC gene exons 5-10, where only one polymorphism of weak diagnostic value is known.

Identification of seven novel missense mutations, two splice-site mutations, two microdeletions and a polymorphic amino acid substitution in the gene for ornithine transcarbamylase (OTC) in patients with OTC deficiency.

Ornithine transcarbamylase (OTC) deficiency, a X-linked disorder, is the most frequent inborn error of the urea cycle. Point mutations and small deletions/insertions in the OTC gene are responsible for the majority of the cases and have a "private" character with little recurrence. We report on eleven pathological changes in the OTC gene sequence detected in three males with mild clinical presentations, and in eight symptomatic females. All of these mutations are novel. Only one mutation affects a CpG mutational hot spot, whereas all but one of the mutations caused an abnormal SSCP of the corresponding PCR-amplified exon. Two mutations occurring in females involved one or two base deletions in codons 196 and 330, respectively, causing frameshift changes and premature termination. Another two mutations in a female and a male affected acceptor splice sites at bases -1 and -3 of the intron 6/exon 7 and intron 9/exon 10 junctions, respectively. All other mutations were point changes causing the simple amino acid substitutions (M1I, I160S, L191F, M206I, L301F, P305H and L341P), although the mutation M1I may abolish translation of the OTC polypeptide. This mutation coexisted in a female patient with the change T333A that appears to be a previously unreported polymorphism. The three male patients but only four of the eight female patients inherited the mutation.

Macromastia: how much of it is fat?

A total of 25 patients who underwent bilateral breast reduction were included in this study. Each patient's age, weight, height, and amount of breast tissue removed from each breast were recorded. The body mass index was calculated for each patient. On the day of the operation, tissue samples (two each) were taken from the central, lateral, and preaxillary areas of the breast. One of the samples was weighed, placed in a closed glass container, and heated for 10 minutes in a microwave oven at full power. The liquid fat was separated from the solid residue, and the percentage of fat was calculated. The other sample from each area was examined grossly, and representative sections, corresponding to the distribution of fat and connective tissue, were submitted for evaluation. In these samples, the percentage of fat, gland, and connective tissue was estimated using low-magnification light microscopy. In this group of patients (who had an average age of 34 years and who were significantly overweight as determined by a mean body mass index of 28), it was found (using the microwave method) that there was a mean fat percentage of 61 percent in the central breast area, 74 percent in the lateral breast area, and 73 percent in the preaxillary area. Upon microscopic examination, the pathologist reported that fat accounted for 64 percent of the central breast area, 92 percent of the lateral breast area, and 94 percent of the preaxillary area. On average, the central breast area in macromastia patients had only seven percent gland and 29 percent connective tissue. The lateral and preaxillary areas of the breast had one to three percent gland and five percent connective tissue. The two methods had a significant (p < 0.05) positive correlation in the central breast area, but in the lateral and preaxillary regions, the correlation was poor. In the microscopic examination, there was a tendency to overestimate the amount of fat. Both methods of evaluation used in the study concur that the enlarged breast of macromastia consists primarily of fat and that the glandular element is rather small.

Metástasis osea de un meningioma angioblastico intracraneal: informe de un caso

Se reporta un caso de metástasis ósea múltiples de un meningioma angioblástico (hemangiopericitoma intracraneal). Desde el punto de vista clínico y patológico, es esencial tener presente que la variante angioblástica del meningioma tiene un mayor índice de recurrencia y metástasis que las otras formas de meningioma

Acquired Immunodeficiency Syndrome(AIDS) and parasitic diseases in Puerto Rico

En Puerto Rico, desde que se hizo el primer diagnóstico de SIDA en 1981, el número de casos y muertes ha ido aumentando progresivamente de 1,253 casos y 741 muertes en mayo 1988 a 1,526 casos y 900 muertes en agosto 2, 1988. En Estados Unidos la mayoría de los casos se diagnostican en varones homosexuales o bisexuales. En Puerto Rico, la mayoría de los casos de SIDA ocurren en varones, heterosexuales y adictos a drogas intravenosas. Las infecciones por parásitos son frecuentes en los pacientes con SIDA en Puerto Rico. Las infecciones parasíticas que se observan con mayor frecuencia son pulmonía por P. carinii y meningoencefalitis por Toxoplasma gondii. Otras menos frecuentes son infección por Schistosoma mansoni y Strongyloides stercovalis. También se ha visto un caso de infección por Isospora belli y dos por Criptosporidium. Estos diagnósticos se hicieron premortem y en la autopsia no se pudieron identificar estos organismos. Este artículo revisa el estado actual de las infecciones por estos parásitos y su diagnóstico en relación con los pacientes de SIDA en Puerto Rico

Es necesario el examen microscópico del sedimento urinario en los análisis de rutina? / Is it necessary the microscopic examination of the urinary sediment in routine urinalysis?

Se evalúam 1,372 análisis de orina, comparando las pruebas químicas, incluyendo esterasas de leucocitos, con el examen microscópico del sedimento urinario y las consecuencias clínicas de no hacer el examen microscópico a las orinas con pruebas químicas normales. De las 1,372 pruebas, 545 tuvieron el análisis químico y el examen microscópico negativo, y 39 tuvieron pruebas químicas negativas y examen microscópico positivo. La sensitividad de las pruebas químicas para detectar alteraciones en el tracto urinario fue de 93% y la especificidad fue de 65%. El valor predictivo positivo fue de 63% y el valor predictivo negativo fue de 93%. Las alteraciones más frecuentes en el sedimiento que no se hubieran detectado con las pruebas químicas solamente fueron: bacterias, hongos y tricomonas químicas solamente fueron: bacterias, hongos y tricomonas, ahora bien no se demostró la utilidad del examen microscópico en estos pacientes. En base a estos datos, se recomienda hacer examen microscópico del sedimiento urinario sólo en aquellos casos de análisis de orina de rutina que presenten alguna ateración en las pruebas químicas