The importance of management in promoting hospital staff's mental well-being during the COVID-19 pandemic-A survey.

AIM: To describe hospital staff's experiences of management actions to promote their mental well-being during the COVID-19 pandemic. Mental well-being was examined on the basis of four entities: level of anxiety, support and encouragement from the manager, and the opportunity to discuss concerns about COVID-19 with the manager. BACKGROUND: The workload of COVID-19 affects the mental well-being of staff. However, there is limited data on managers' actions to promote their mental well-being during the pandemic. METHODS: A cross-sectional study was used to collect survey data (n = 1995) among staff working in two specialized medical care hospitals. To gain deeper understanding related issues, the survey included open questions, which were answered by 178 participants. RESULTS: The results indicate that those staff who felt they had received support, encouragement, and the opportunity to discuss of COVID-19 worries with a manager experienced less anxiety. CONCLUSIONS: The study provides an insight into managers' actions to promote staff's mental well-being during the COVID-19 pandemic. IMPLICATIONS FOR NURSING MANAGEMENT: The manager's actions have a significant effect on the anxiety levels of staff. During the pandemic, the well-being of staff is a priority that should be visible to both hospital administrators and policymakers.

COVID-19: anxiety among hospital staff and associated factors.

BACKGROUND: During the COVID-19 pandemic, hospital staff have experienced a variety of mental health challenges. European research on anxiety and stress among hospital workers during the pandemic is limited. This study aimed to describe the anxiety levels of Finnish hospital workers during the COVID-19 pandemic. METHODS: The multidimensional, cross-sectional survey was distributed to all hospital staff working at two Finnish specialized medical care centres in the spring of 2020 (n = 1,995). The Generalized Anxiety Disorder 7-item (GAD-7) scale was used to measure the workers' anxiety. RESULTS: The total mean GAD-7 score was 4.88, indicating normal anxiety levels. However, 30% (n = 1,079) of the respondents had mild, 10% (n = 194) moderate and 5% (n = 88) severe anxiety. Key risk factors were young age, working in a university hospital, problems in cooperation between co-workers, difficulty concentrating at work, a health-threatening physical and psychological workload, and a fear of being infected at work. CONCLUSION: Hospital staff experienced a variety of work-related stress and anxiety issues that should be visible to hospital administrators and policymakers alike. The anxiety is independent of whether the worker is directly involved in caring for or in any way coming into contact with COVID-19 patients. Key message Fifty-five percent of hospital staff have normal anxiety levels. The remaining workers may need targeted support interventions, and a smaller proportion (15%) are in danger of developing longer-term problems affecting their well-being. The anxiety experienced by hospital workers during the COVID-19 pandemic is more severe than that of the population on average. If the pandemic continues, the well-being of hospital staff may be widely threatened. Despite the different geographical locations and COVID-19 situations, hospital workers in Finland and China had similar anxiety levels. The anxiety is independent of whether staff are working in the front line of managing the COVID-19 pandemic or of the number of covid-19 patients admitted to the hospital. The hospital workers felt anxiety because they were facing a new situation which causes changes in their work and daily routine. Health care employers should engage in long-term follow-up as regards the personnel's recovery from the burden caused by the pandemic and from work in general. It is necessary to make easily attainable, flexibly delivered and cost-effective treatment interventions for anxiety available to hospital staff.

Occurrence and Recovery of Different Neglect-Related Symptoms in Right Hemisphere Infarct Patients during a 1-Year Follow-Up.

OBJECTIVES: To examine the occurrence of and recovery from visual neglect-related symptoms with the focus on neglect laterality, ipsilateral orienting bias, and slowed processing speed in right hemisphere (RH) infarct patients during a 1-year follow-up. Furthermore, to propose guidelines for assessing processing speed alongside the Behavioural Inattention Test (BIT). METHODS: We studied three RH patient groups: neglect (N+), mild left inattention (MLI+), and non-neglect (N-) patients, and healthy controls. The BIT with some additional analyses was conducted at the acute phase and at 6 and 12 months. RESULTS: The N+ group's BIT score increased and originally lateralized omissions became more evenly distributed during the follow-up. The N+ and MLI+ groups' starting points were more rightward located than the healthy group's at the acute phase and at 6, and partly at 12 months. Patient groups were slower than the controls in performing cancellation tests at the acute phase. The N+ and MLI+ groups remained slower than the controls throughout the follow-up. CONCLUSIONS: During the first year after RH infarct, originally left-sided manifestation of neglect shifted toward milder non-lateralized attentional deficit. Ipsilateral orienting bias and slowed processing speed appeared to be rather persistent neglect-related symptoms both in neglect patients and patients with initially milder inattention. We propose some effortless, tentative ways of examining processing speed and ipsilateral orienting bias alongside the BIT to better recognize these neglect-related symptoms, and highlight the need to assess and treat patients with initially milder inattention, who have been under-recognized and under-treated in clinical work. (JINS, 2018, 24, 617-628).

Factors Influencing Quality of Life Six Months after a First-Ever Ischemic Stroke: Focus on Thrombolyzed Patients.

OBJECTIVE: This prospective follow-up study aimed to identify sociodemographic and clinical factors that may affect the quality of life (QoL) of patients with acute ischemic stroke during a 6-month follow-up. PATIENTS AND METHODS: In the acute phase, sociodemographic and clinical data were collected using the National Institute of Health Stroke Scale, Barthel Index, and modified Rankin Scale. QoL was assessed with the Stroke and Aphasia Quality of Life Scale-39 6 months after stroke. RESULTS: QoL was evaluated in 64 patients (aged 45-81 years) with a first-ever ischemic stroke. Thrombolytic therapy was given to 80% of the patients. Stroke severity, dependence in activities of daily living, degree of handicap, and length of hospitalization were associated with QoL. QoL was not associated with age, gender, marital status, or years of education. CONCLUSION: In this study, most patients were treated with thrombolysis, and QoL results resembled those of earlier studies on patients without thrombolysis. Despite good physical recovery, the patients reported impairments in QoL. QoL assessments can give clinicians a more holistic picture of stroke recovery from the patient's perspective.

Symptomatic intracranial hemorrhage after stroke thrombolysis: comparison of prediction scores.

BACKGROUND AND PURPOSE: Several prognostic scores have been developed to predict the risk of symptomatic intracranial hemorrhage (sICH) after ischemic stroke thrombolysis. We compared the performance of these scores in a multicenter cohort. METHODS: We merged prospectively collected data of patients with consecutive ischemic stroke who received intravenous thrombolysis in 7 stroke centers. We identified and evaluated 6 scores that can provide an estimate of the risk of sICH in hyperacute settings: MSS (Multicenter Stroke Survey); HAT (Hemorrhage After Thrombolysis); SEDAN (blood sugar, early infarct signs, [hyper]dense cerebral artery sign, age, NIH Stroke Scale); GRASPS (glucose at presentation, race [Asian], age, sex [male], systolic blood pressure at presentation, and severity of stroke at presentation [NIH Stroke Scale]); SITS (Safe Implementation of Thrombolysis in Stroke); and SPAN (stroke prognostication using age and NIH Stroke Scale)-100 positive index. We included only patients with available variables for all scores. We calculated the area under the receiver operating characteristic curve (AUC-ROC) and also performed logistic regression and the Hosmer-Lemeshow test. RESULTS: The final cohort comprised 3012 eligible patients, of whom 221 (7.3%) had sICH per National Institute of Neurological Disorders and Stroke, 141 (4.7%) per European Cooperative Acute Stroke Study II, and 86 (2.9%) per Safe Implementation of Thrombolysis in Stroke criteria. The performance of the scores assessed with AUC-ROC for predicting European Cooperative Acute Stroke Study II sICH was: MSS, 0.63 (95% confidence interval, 0.58-0.68); HAT, 0.65 (0.60-0.70); SEDAN, 0.70 (0.66-0.73); GRASPS, 0.67 (0.62-0.72); SITS, 0.64 (0.59-0.69); and SPAN-100 positive index, 0.56 (0.50-0.61). SEDAN had significantly higher AUC-ROC values compared with all other scores, except for GRASPS where the difference was nonsignificant. SPAN-100 performed significantly worse compared with other scores. The discriminative ranking of the scores was the same for the National Institute of Neurological Disorders and Stroke, and Safe Implementation of Thrombolysis in Stroke definitions, with SEDAN performing best, GRASPS second, and SPAN-100 worst. CONCLUSIONS: SPAN-100 had the worst predictive power, and SEDAN constantly the highest predictive power. However, none of the scores had better than moderate performance.

Relationship between onset-to-door time and door-to-thrombolysis time: a pooled analysis of 10 dedicated stroke centers.

BACKGROUND AND PURPOSE: Inverse relationship between onset-to-door time (ODT) and door-to-needle time (DNT) in stroke thrombolysis was reported from various registries. We analyzed this relationship and other determinants of DNT in dedicated stroke centers. METHODS: Prospectively collected data of consecutive ischemic stroke patients from 10 centers who received IV thrombolysis within 4.5 hours from symptom onset were merged (n=7106). DNT was analyzed as a function of demographic and prehospital variables using regression analyses, and change over time was considered. RESULTS: In 6348 eligible patients with known treatment delays, median DNT was 42 minutes and kept decreasing steeply every year (P<0.001). Median DNT of 55 minutes was observed in patients with ODT ≤30 minutes, whereas it declined for patients presenting within the last 30 minutes of the 3-hour time window (median, 33 minutes) and of the 4.5-hour time window (20 minutes). For ODT within the first 30 minutes of the extended time window (181-210 minutes), DNT increased to 42 minutes. DNT was stable for ODT for 30 to 150 minutes (40-45 minutes). We found a weak inverse overall correlation between ODT and DNT (R(2)=-0.12; P<0.001), but it was strong in patients treated between 3 and 4.5 hours (R(2)=-0.75; P<0.001). ODT was independently inversely associated with DNT (P<0.001) in regression analysis. Octogenarians and women tended to have longer DNT. CONCLUSIONS: DNT was decreasing steeply over the last years in dedicated stroke centers; however, significant oscillations of in-hospital treatment delays occurred at both ends of the time window. This suggests that further improvements can be achieved, particularly in the elderly.

Brain phenotype of carbonic anhydrase IX-deficient mice.

Preliminary observations have suggested mild behavioral changes and a morphological disruption of brain histology in 1.5-year-old carbonic anhydrase IX (CA IX)-deficient (Car9 (-/-)) mice. These findings led us to design a 1-year follow-up study in which the behavior and brain histology of Car9 (-/-) and wild-type mice were monitored. Morphological analysis revealed vacuolar degenerative changes in the brains of Car9 (-/-) mice. The changes became visible at the age of eight to ten months. Behavioral tests showed that the Car9 (-/-) mice exhibited abnormal locomotor activity and poor performance in a memory test. To further identify the transcriptomic responses to CA IX deficiency in the brain, genome-wide cDNA microarray analyses were performed. Thirty-one and 37 genes were significantly up- or down-regulated, respectively, in the brain of Car9 (-/-) mice compared to the wild-type mice. Functional annotation revealed that the genes with increased expression were involved in several processes, such as RNA metabolism, and the genes with reduced expression were implicated in other important processes, including the regulation of cellular ion homeostasis. Notably, the biological processes "behavior" and "locomotory behavior" were the two prominent terms overrepresented among the down-regulated genes, which is consistent with the behavioral phenotype. These results suggest that CA IX may directly or indirectly play novel functions in brain tissue. Furthermore, the brain phenotype of Car9 (-/-) mice seems to be age-dependent. The results indicate that the functional changes precede the microscopic alterations in the brains of Car9 (-/-) mice.

The tumour-associated carbonic anhydrases CA II, CA IX and CA XII in a group of medulloblastomas and supratentorial primitive neuroectodermal tumours: an association of CA IX with poor prognosis.

BACKGROUND: Medulloblastomas (MBs) and supratentorial primitive neuroectodermal tumours (PNETs) are the most common highly aggressive paediatric brain tumours. In spite of extensive research on these tumours, there are only few known biomarkers or therapeutic target proteins, and the prognosis of patients with these tumours remains poor. Our aim was to investigate whether carbonic anhydrases (CAs), enzymes commonly overexpressed in various tumours including glioblastomas and oligodendrogliomas, are present in MBs and PNETs, and whether their expression can be correlated with patient prognosis. METHODS: We determined the expression of the tumour-associated carbonic anhydrases CA II, CA IX and CA XII in a series of MB/PNET specimens (n = 39) using immunohistochemistry. RESULTS: Endothelial CA II, cytoplasmic CA II, CA IX and CA XII were expressed in 49%, 73%, 23% and 11% of the tumours, respectively. CA II was detected in the neovessel endothelium and the tumour cell cytoplasm. CA IX was mainly expressed in the tumour cells located in perinecrotic areas. CA XII showed the most homogenous distribution within the tumours. Importantly, CA IX expression predicted poor prognosis in both univariate (p = 0.041) and multivariate analyses (p = 0.016). CONCLUSIONS: We suggest that CA IX should be considered a potential prognostic and therapeutic target in MBs and PNETs.

Carbonic anhydrase II. A novel biomarker for gastrointestinal stromal tumors.

Gastrointestinal stromal tumors (GISTs) are clinically distinct mesenchymal tumors, which generally result from expression of mutant KIT or PDGFRA receptor tyrosine kinase oncogenes. Most GISTs feature strong expression of KIT that serves as a crucial diagnostic adjunct. However, a subset of tumors lacks KIT expression and otherwise may also be difficult to distinguish from other sarcomas, including leiomyosarcoma. Because various carbonic anhydrase (CA) isozymes have been identified as potential treatment targets against different cancers, we evaluated CA II expression in 175 GISTs. Western blotting experiments indicated that CA II is highly expressed in GIST cell lines. Immunohistochemically, 95% of GISTs showed positive signal. The CA II expression in GISTs did not correlate with particular KIT or PDGFRA mutation types. CA II immunoreactivity was absent or low in other mesenchymal tumor categories analyzed. High CA II expression was associated with a better disease-specific survival rate than low or no expression (Mantel-Cox test, P<0.0001). The present results indicate that CA II is overexpressed in most GISTs, is quite selective to this tumor type among mesenchymal tumors, and therefore might be a useful biomarker in diagnostics.

Carbonic anhydrases in meningiomas: association of endothelial carbonic anhydrase II with aggressive tumor features.

OBJECT: Carbonic anhydrase (CA) II and IX are enzymes involved in pH homeostasis and have been shown to be upregulated in several types of cancer. In this study, the authors evaluate the expression of CA II and IX in meningiomas and assess their relationship to patient age, tumor type and grade, tumor sex hormone receptor status, tumor cell proliferation, and tumor recurrence. METHODS: This study was conducted in consecutive patients who underwent meningioma surgeries at Tampere University Hospital between 1989 and 1999. The expression of CA II and IX was studied immunohistochemically using a tissue microarray technique and specific antibodies. RESULTS: Immunohistological staining with CA II and IX was assessed in 443 primary and 67 recurrent tumor specimens. Of these samples, 455 were benign (WHO Grade I), 49 atypical (Grade II), and 6 malignant (Grade III). Endothelial cells in 14.8% of the tumors stained positively for CA II. Tumor cells were positive for CA IX in 11.6% of the cases. Endothelial CA II expression correlated with increasing histological grade (p=0.002), and tumor proliferation rates were higher in CA II+ versus CA II- cases (p=0.002). Androgen receptor-negative tumors were found to be CA II+ significantly more often than androgen receptor-positive tumors (p=0.001). No associations were found with the CA IX enzyme. CONCLUSIONS: Carbonic anhydrase II positivity in the endothelium was associated with cell proliferation and malignancy grade. These results suggest that CA II expression is associated with malignant progression of meningiomas and could thus be a target molecule for anticancer therapy.

Identification of an alternatively spliced isoform of carbonic anhydrase XII in diffusely infiltrating astrocytic gliomas.

Carbonic anhydrase XII (CA XII) is a transmembrane enzyme that is associated with neoplastic growth. CA XII has been proposed to be involved in acidification of the extracellular milieu, creating an appropriate microenvironment for rapid tumor growth. Because RNA sequence databases have indicated that two isoforms of CA XII might exist in human tissues, and because alternatively spliced protein forms have been linked to aggressive behavior of cancer cells, we designed a study to evaluate the presence of the two forms of CA XII in diffuse astrocytomas, a tumor type known for its aggressive and often noncurable behavior. Reverse transcription PCR of tumor samples surprisingly revealed that CA XII present in diffuse astrocytomas is mainly encoded by a shorter mRNA variant. We further showed by Western blotting that anti-CA XII antibody recognized both isoforms in the glioblastoma cell lines, and we then evaluated the expression of CA XII in astrocytomas using immunohistochemistry and correlated the results with various clinicopathological and molecular factors. Of 370 diffusely infiltrating astrocytomas, 363 cases (98%) showed immunoreactions for CA XII. Importantly, CA XII expression correlated with poorer patient prognosis in univariate (p = 0.010, log-rank test) and multivariate survival analyses (p = 0.039, Cox analysis). From these results, we conclude that CA XII is commonly expressed in diffuse astrocytomas and that it might be used as a biomarker of poor prognosis. The absence of 11 amino acids in the shorter isoform, which seems to be common in astrocytomas, may affect the normal quaternary structure and biological function of CA XII.

Carbonic anhydrase IX in oligodendroglial brain tumors.

BACKGROUND: Carbonic anhydrase IX is a hypoxia-induced enzyme that has many biologically important functions, including its role in cell adhesion and invasion. METHODS: This study was set out to investigate the role of CA IX in a series of 86 oligodendroglial brain tumors (71 primary and 15 recurrent; 48 pure oligodendrogliomas and 40 mixed oligoastrocytomas). RESULTS: 80% of the tumors showed CA IX expression by immunohistochemistry. Tumors with moderate or strong CA IX expression had decreased level of cell proliferation compared to weak or no CA IX expression (median 2.9 vs. 5.8, p = 0.015). CA IX correlated with two antioxidative enzymes, manganese superoxide dismutase (MnSOD) and regulatory gammaglutamylcysteine synthetase (GLCL-R): CA IX expression was significantly higher in MnSOD-positive tumors (p = 0.008) and decreased in GLCL-R-positive tumors (p = 0.044). In Cox multivariate analysis CA IX expression, patient age and histological component (pure oligodendroglioma vs. mixed oligoastrocytoma) showed independent prognostic values (p = 0.009, p = 0.003 and p = 0.022, respectively), CA IX positivity predicting poorer outcome. CONCLUSION: CA IX was proved to be an independent prognostic indicator in oligodendroglial brain tumors, and it also correlates reversely with cell proliferation. It may have a role in the biology of oligodendrogliomas, and most interestingly, as it is mainly expressed in tumor tissue, CA IX could serve as a target molecule for anticancer treatments.

Carbonic anhydrase IX is highly expressed in hereditary nonpolyposis colorectal cancer.

Carbonic anhydrase (CA) II, CA IX, and CA XII are expressed in various neoplasias and have been linked to tumorigenesis. We examined their expression in three different groups of colorectal cancer [i.e., microsatellite stable (MSS), microsatellite instable (MSI), and hereditary nonpolyposis colorectal cancer (HNPCC)]. First, we analyzed gene expression profiles of 113 specimens by a microarray method to study the expression of various CA isozymes in the subgroups of colorectal cancer. The results indicated that mRNAs for CA II and CA XII are down-regulated and CA IX mRNA is up-regulated in all three tumor categories when compared with the normal tissue. The up-regulation of CA IX was greatest in the HNPCC group. For more information, 77 specimens were immunohistochemically stained to study the levels of CA II, CA IX, and CA XII. Immunohistochemical analyses further confirmed that the subgroups express CA II, CA IX, and CA XII differentially, and the HNPCC tumors express high levels of CA IX. Expression of these CAs did not correlate to Dukes stage or grade of differentiation. Our results show that CAs are differentially expressed in the subgroups of colorectal cancer, and CA IX expression seems to be very high in most cases of HNPCC. CA IX could be a potential diagnostic and therapeutic target in HNPCC.

Carbonic anhydrase II in the endothelium of glial tumors: a potential target for therapy.

Carbonic anhydrase isozyme II (CA II) is a cytosolic enzyme that is highly expressed in most organs, including the brain, where it is mainly located in the oligodendrocytes. Recent studies have shown that its expression is induced in the endothelium of neovessels in melanoma and esophageal, renal, and lung cancer. Immunological studies further indicate that CA II represents a major target antigen stimulating an autoantibody response in melanoma patients. These results prompted us to investigate endothelial CA II expression in two types of brain cancer: oligodendrogliomas and astrocytomas. A series of 255 astrocytoma and 71 oligodendroglial tumor specimens was immunostained for CA II. The staining results were correlated with a number of different clinicopathological factors and survival data. CA II showed weak or no expression in low-grade tumors, while grade 3 mixed oligoastrocytoma and glioblastoma multiforme were the most positively stained tumor types. Survival analysis indicated that endothelial CA II staining is significantly associated with a poor prognosis in patients with astrocytomas. About 17% of patients with CA II-negative tumors (weak or no endothelial signal) were still alive at the end of the follow-up period of five years. The presence of CA II in the tumor endothelium suggests that it may play an important functional role in tumor metabolism. From a clinical perspective, the results also open new avenues for selecting tumor types for dendritic cell therapy trials.

Carbonic anhydrase activators: activation of isozyme XIII with amino acids and amines.

The first activation study of isoform XIII of carbonic anhydrase (CA, EC 4.2.1.1) is reported. A series of amino acids and amines incorporating protonatable moieties of the primary/heterocyclic amine type were included in the study. As for CA I and II, CA XIII activators enhance kcat and show no effect on KM, for the physiologic reaction catalyzed by this isoform. Excellent CA XIII activating properties were shown by D-amino acids (His, Phe, DOPA, and Trp), serotonin, and 4-(2-aminoethyl)-morpholine, whereas the corresponding L-amino acids, dopamine, histamine, and 1-(2-aminoethyl)-piperazine, were weaker activators.

Expression of carbonic anhydrase IX in astrocytic tumors predicts poor prognosis.

PURPOSE: Carbonic anhydrase IX (CA IX) is a hypoxia-inducible enzyme, which is associated with neoplastic growth. Ectopic CA IX expression has been observed in several tumors, whose normal counterparts do not express this enzyme. Normal human brain tissue shows only slight or no expression of CA IX. EXPERIMENTAL DESIGN: We describe CA IX expression in human diffusely infiltrating astrocytomas. The association of CA IX is evaluated with clinicopathologic and molecular factors including cell proliferation and apoptosis as well as the expression of p53 and epidermal growth factor receptor. RESULTS: CA IX immunopositivity was observed in 284 cases of 362 (78%) tumors. The positive areas were often located in close proximity to necrotic regions (P < 0.001). The CA IX immunoreactivity showed strong association with tumor malignancy grades (P < 0.0001). CA IX showed no association with p53 expression nor did it correlate with epidermal growth factor receptor-amplification, apoptosis, or cell proliferation. CA IX intensity had significant prognostic value in univariate (P=0.0011, log-rank test) and multivariate survival analysis (P = 0.038, Cox analysis). CONCLUSIONS: CA IX expression is common in diffusely infiltrating high-grade astrocytomas. Our results suggest that CA IX is a useful biomarker for predicting poor prognosis of astrocytic tumors. It may also be a promising target molecule for the improvement of therapeutic interventions in astrocytomas.

Expression of von Hippel-Lindau tumor suppressor and tumor-associated carbonic anhydrases IX and XII in normal and neoplastic colorectal mucosa.

AIM: To analyze possible relationships between CA IX/CA XII and pVHL expression in normal and neoplastic colorectal mucosa. METHODS: Immunohistochemical staining of 42 tissue specimens obtained from 17 cancer patients was performed to evaluate the distribution and semi-quantitatively assess the levels of CA IX, CA XII and pVHL. VHL mRNAs from 14 fresh-frozen tumors was amplified by RT-PCR and subjected to sequencing. CA9 and CA12 mRNA levels were analyzed by semi-quantitative RT-PCR in comparison with VEGF as an indicator of hypoxia that uncouples the pVHL control. RESULTS: Tumor tissues were associated with a borderline increase of CA IX staining signal and slight but significant decrease of CA XII immunoreactivity, whereas no association was found for pVHL. Sequence analysis of RT-PCR-amplified VHL mRNAs revealed no deletions/mutations, suggesting that they were VHL-competent. We did not observe any correlation between pVHL and CA IX/CA XII proteins as well as between VEGF and CA9 mRNAs, but the tumor-associated changes in mRNA levels of VEGF and CA12 showed a significant inverse relationship. CONCLUSION: Our results indicate that CA9 and CA12 are regulated by different intratumoral factors and that lack of apparent relationship between the levels of CA IX/CA XII and pVHL cannot be fully assigned to uncoupling of negative regulatory function of pVHL by tumor hypoxia signified by induced VEGF transcription. The interplay between the functional pVHL and CA IX/CA XII in colorectal tumors seems rather complex and is not evident merely at the expression levels.

Characterization of CA XIII, a novel member of the carbonic anhydrase isozyme family.

The carbonic anhydrase (CA) gene family has been reported to consist of at least 11 enzymatically active members and a few inactive homologous proteins. Recent analyses of human and mouse databases provided evidence that human and mouse genomes contain genes for still another novel CA isozyme hereby named CA XIII. In the present study, we modeled the structure of human CA XIII. This model revealed a globular molecule with high structural similarity to cytosolic isozymes, CA I, II, and III. Recombinant mouse CA XIII showed catalytic activity similar to those of mitochondrial CA V and cytosolic CA I, with k(cat)/K(m) of 4.3 x 10(7) m(-1) s(-1), and k(cat) of 8.3 x 10(4) s(-1). It is very susceptible to inhibition by sulfonamide and anionic inhibitors, with inhibition constants of 17 nm for acetazolamide, a clinically used sulfonamide, and of 0.25 microm, for cyanate, respectively. Using panels of cDNAs we evaluated human and mouse CA13 gene expression in a number of different tissues. In human tissues, positive signals were identified in the thymus, small intestine, spleen, prostate, ovary, colon, and testis. In mouse, positive tissues included the spleen, lung, kidney, heart, brain, skeletal muscle, and testis. We also investigated the cellular and subcellular localization of CA XIII in human and mouse tissues using an antibody raised against a polypeptide of 14 amino acids common for both human and mouse orthologues. Immunohistochemical staining showed a unique and widespread distribution pattern for CA XIII compared with the other cytosolic CA isozymes. In conclusion, the predicted amino acid sequence, structural model, distribution, and activity data suggest that CA XIII represents a novel enzyme, which may play important physiological roles in several organs.

Monoclonal antibodies generated in carbonic anhydrase IX-deficient mice recognize different domains of tumour-associated hypoxia-induced carbonic anhydrase IX.

Transmembrane carbonic anhydrase IX (CA IX) is frequently expressed in human tumours in response to hypoxia and may serve as a tumour marker and therapeutic target. So far, only a single monoclonal antibody (MAb) M75 with an epitope in the N-terminal proteoglycan (PG)-like region has been available for detection purposes. Attempts to produce MAbs against other parts of CA IX were unsuccessful due to the immunodominance of the PG region that significantly differs between human and mouse homologues. To overcome this problem, we used various forms of human CA IX antigen to immunize CA IX-deficient mice recently produced by targeted disruption of Car9 gene. Here, we describe new MAbs that react with human, but not mouse CA IX in different immunodetection settings, and show no cross-reactivity with CA I, II and XII. MAb IV/18 is directed to the PG region, while the other six antibodies bind to the CA domain, as determined by CA IX deletion variants. IV/18 recognizes a linear epitope, while anti-CA MAbs V/10, V/12, VII/20, VII/28, VII/32 and VII/38 react with conformational epitopes clustered into three antigenic sites. The new antibodies represent important tools for improving our knowledge of structure-function relationships in the CA IX molecule and a better understanding of the role of CA IX in cancer development. Moreover, the availability of the MAbs specific for distinct antigenic regions on two separate extracellular domains offers an opportunity to elaborate a sensitive assay that could be particularly important for CA IX detection in body fluids of cancer patients.

Clinical utility and outcome of HFE-genotyping in the search for hereditary hemochromatosis.

BACKGROUND: Hereditary hemochromatosis (HH), a disease involving iron accumulation in internal organs, occurs in about 1 in 200-400 Caucasians. The gene mutated in this disorder is termed HFE. The present study was designed to evaluate the diagnostic utility and outcome of genetic testing for HH in the service of public health care. METHODS: 137 subjects were referred by health clinics and general hospitals for HFE genotyping from various parts of Finland during the period 1999-2001. Two major mutations (C282Y and H63D) were determined for each patient. Reasons contributing to referrals and sets of values for serum transferrin saturation (s-TS) and iron and ferritin concentrations were also determined. RESULTS: 16.8% of the subjects were homozygous for the C282Y mutation, together with seven C282Y/H63D compound heterozygotes (5.1%). The rate of positive findings for the most typical mutations responsible for HH was found to have increased steadily during the period 1999-2001. CONCLUSIONS: Our data support a role for active testing for the C282Y and H63D mutations in health care. The fairly low number of genotyping requests nevertheless suggests that a large number of patients even with typical clinical signs or symptoms continue to escape detection.