Adverse health outcomes and health concerns among survivors of various childhood cancers: Perspectives from mothers.

Advanced therapies have improved outcomes and also resulted in a growing risk of long-term adverse health events. This study intends to estimate incidences of adverse health events and examine differences in adverse health events among childhood cancer survivors, and to understand the concerns of mothers after their child has completed cancer treatment. An explanatory sequential mixed-method was used. A total of 201 paediatric cancer survivors' mothers with mean age 43.6 years were recruited. Of the survivors, 12.4% experienced five or more adverse health events. The incidence of adverse health events of altered body image, fatigue and neurocognitive problems were 31.54%, 14.77% and 12.53% respectively. Among survivors, significant differences in adverse health events of pain, endocrine problems and altered body image issues were identified. Survivors receiving radiotherapy, bone marrow transplants or completing treatment after 6-10 years experienced significantly more adverse health events. Maintaining health was the greatest concern for mothers, and the qualitative reports of their concerns could be categorised: living in uncertainty, and keeping forward-looking. Childhood brain tumour survivors were identified as experiencing more adverse health events than other survivors. The need for healthcare teams to consider mothers' health concerns was highlighted.

Risk factors influencing the outcome of peptic ulcer bleeding in end stage renal diseases after initial endoscopic haemostasis.

Background and Aims: Patients suffering from peptic ulcer (PU) bleeding who have end-stage renal disease (ESRD) may encounter more adverse outcomes. The primary objective is to investigate the risk factors that influence the outcomes of ESRD and chronic kidney disease (CKD) patients with PU bleeding after successful initial endoscopic haemostasis. Methods: A total of 540 patients with PU bleeding after initial endoscopic haemostasis in a tertiary hospital were investigated retrospectively. They were sorted into three groups after randomised age-matched adjustment: ESRD group (n = 90), CKD group (n = 90) and control group (n = 360). Main outcome measurements were rebleeding, requirement for blood transfusion and surgery, length of hospital stay and mortality. Results: The rebleeding rates were 43% for the ESRD group vs. 21% for the CKD group vs. 12% for the control group (overall p = < 0.001). Multivariate analysis showed the predictors of rebleeding were ESRD, time to endoscope, and non-high-dose proton-pump inhibitors (PPI) users. The risk factors for bleeding-related mortality were presence of moderate degree of CKD and ESRD group, time to endoscope, and Rockall score. All-cause mortality was related to presence of moderate degree of CKD and ESRD group, platelet count, time to endoscope, Rockall score and length of hospital stay. Conclusions: ESRD patients who suffered from PU bleeding were at risk of excessive rebleeding and mortality with frequent occurrence of delayed rebleeding. This study suggests that early endoscopy for initial haemostasis and high-dose intravenous PPI are associated with the reduction of rebleeding risk especially in patients with high Rockall scores.

Effect of chewing a single betel-quid on autonomic nervous modulation in healthy young adults.

Betel-quid is widely used around the world as a stimulant for the autonomic nervous system. The aim of this study was to assess the effect of betel-quid chewing on autonomic nervous modulation by using spectral heart rate variability (HRV) analysis. Twenty healthy young adults were included in this study. Each subject chewed a single betel-quid containing one betel nut or a piece of chewing-gum for 60 min on different days in random order. Spectral HRV measures were obtained before, and 5, 30 and 60 min after starting to chew betel-quid or gum. Sequential changes in HRV measures were compared between chewing gum and betel-quid. Heart rate was significantly elevated after 5 min chewing betel-quid, but not after chewing gum. The normalized low-frequency power and low-/high-frequency power ratio were elevated after 5 min chewing gum or betel-quid; however, the normalized high-frequency power was reduced after 5 min chewing gum or betel-quid. The percentage changes in total power after 5, 30 and 60 min chewing betel-quid were significantly lower than those after chewing gum. This study confirms that novice chewing of betel-quid modulates autonomic nervous system activity; transiently enhancing sympathetic activity and gradually suppressing vagal activity in healthy young adults.

Molecular basis of spectrin deficiency in beta spectrin Durham. A deletion within beta spectrin adjacent to the ankyrin-binding site precludes spectrin attachment to the membrane in hereditary spherocytosis.

We describe a spectrin variant characterized by a truncated beta chain and associated with hereditary spherocytosis. The clinical phenotype consists of a moderate hemolytic anemia with striking spherocytosis and mild spiculation of the red cells. We describe the biochemical characteristics of this truncated protein which constitutes only 10% of the total beta spectrin present on the membrane, resulting in spectrin deficiency. Analysis of reticulocyte cDNA revealed the deletion of exons 22 and 23. We show, using Southern blot analysis, that this truncation results from a 4.6-kb genomic deletion. To elucidate the basis for the decreased amount of the truncated protein on the membrane and the overall spectrin deficiency, we show that (a) the mutated gene is efficiently transcribed and its mRNA abundant in reticulocytes, (b) the mutant protein is normally synthesized in erythroid progenitor cells, (c) the stability of the mutant protein in the cytoplasm of erythroblasts parallels that of the normal beta spectrin, and (d) the abnormal protein is inefficiently incorporated into the membrane of erythroblasts. We conclude that the truncation within the beta spectrin leads to inefficient incorporation of the mutant protein into the skeleton despite its normal synthesis and stability. We postulate that this misincorporation results from conformational changes of the beta spectrin subunit affecting the binding of the abnormal heterodimer to ankyrin, and we provide evidence based on binding assays of recombinant synthetic peptides to inside-out-vesicles to support this model.

Transcription factor SPZ1 promotes TWIST-mediated epithelial-mesenchymal transition and oncogenesis in human liver cancer.

The epithelial-mesenchymal transition (EMT) is an important process in the progression of cancer. However, its occurrence and mechanism of regulation are not fully understood. We propose a regulatory pathway in which spermatogenic leucine zipper 1 (SPZ1) promotes EMT through its transactivating ability in increasing TWIST1 expression. We compared the expression of SPZ1 and TWIST1 in specimens of hepatocarcinoma cells (HCCs) and non-HCCs. Expression of SPZ1 exhibited a tumor-specific expression pattern and a high correlation with patients' survival time, tumor size, tumor number and progression stage. Moreover, forced expression and knockdown of SPZ1 in hepatoma cells showed that SPZ1 was able to regulate the cellular proliferation, invasion, and tumorigenic activity in a TWIST1-dependent manner in vitro and in vivo. These data demonstrate that SPZ1, a newly dscribed molecule, transactivates TWIST1 promoters, and that this SPZ1-TWIST axis mediates EMT signaling and exerts significant regulatory effects on tumor oncogenesis.

RS-66271, a C-terminally substituted analog of human parathyroid hormone-related protein (1-34), increases trabecular and cortical bone in ovariectomized, osteopenic rats.

It was predicted from the amino acid sequence of the bone anabolic peptides, parathyroid hormone (PTH) (1-34) and PTH related protein (PTHrP) (1-34), that the C-terminal amino acids form an amphipathic alpha-helix. Therefore, we substituted a model amphipathic alpha-helical peptide (MAP) sequence in the C-terminal region of hPTHrP(1-34), obtaining RS-66271 ([MAP1-10]22-31 hPTHrP(1-34)-NH2). The anabolic activities of RS-66271 and hPTHrP(1-34) were evaluated in 3-month-old, ovariectomized (OVX) osteopenic rats. Subcutaneous injection of hPTHrP(1-34) at 80 micrograms/kg/day partially reversed estrogen depletion trabecular bone loss but was ineffective in the cortex. In contrast, RS-66271 dose-relatedly reversed loss at both sites and, at 80 micrograms/kg/day, returned both trabecular and cortical bone calcium to the level of sham-operated controls. Histomorphometric analysis showed significantly elevated bone formation rates over vehicle-treated OVX in both trabecular and cortical tibial bone following treatment with RS-66271. Electron microscopy showed an increase in the relative surface area of vertebral trabeculae covered by osteoblasts in animals treated with RS-66271. These studies demonstrate that the C-terminal amino acids of hPTHrP(1-34) can be replaced by a model amphipathic helix and that the new chemical entity has greater anabolic activity than the parent peptide. The results suggest that RS-66271 may be a candidate molecule for the treatment of human osteoporosis.

Modulation of the membrane surrounding particulate cement and polyethylene in the rabbit tibia.

Twenty-nine mature New Zealand white, female rabbits were divided into four groups. Using sterile technique, a 6 mm drill hole was made in the tibia 1 cm distal to the knee joint. The marrow was scooped out underneath the hole. The right tibia received Simplex particulate cement polymer (PMMA) (groups 1 and 2) or polyethylene particles (UHMWP) (groups 3 and 4). The left leg functioned as a prepared but non-implanted control. All animals were fed a standard diet; those in groups 1 and 3 received plain water, while groups 2 and 4 drank water in which sodium naproxen was dissolved (1.375 mg/ml). Animals were killed after 16 wk. The implant area was harvested and grown in tissue culture. The cumulative collection of tissue culture supernatants over 3 d was assayed for prostaglandin E2 (PGE2) via radioimmunoassay. PGE2 production was significantly higher in the membrane harvested from the right side containing particulate cement with no sodium naproxen (group 1) compared with controls (P less than 0.05). The ratio of PGE2 values for the right divided by the left side yielded higher values in group 1, compared with groups 2, 3 or 4 (P less than 0.01). Previous studies have suggested that particulate debris and PGE2 production are associated with arthroplasty loosening. This experiment has demonstrated that PGE2 production by the membrane surrounding particulate debris can be suppressed by the administration of oral sodium naproxen. Because non-steroidal anti-inflammatory drugs are known to inhibit prostaglandin synthesis in man, these agents may prove useful in retarding the bone loss associated with early prosthetic loosening.

Liver biochemical tests and dengue fever.

The impact of dengue on liver function was studied by biochemical tests on 125 male and 145 female patients diagnosed with this disease during an outbreak that extended from November 1987 to December 1988. Abnormal levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin, alkaline phosphatase, and gamma-glutamyl transpeptidase (G-GT) were observed in 93.3%, 82.2%, 7.2%, 16.3% and 83.0% of the patients, respectively. The elevation of transaminases was mild to moderate in most cases, but was 10-fold greater than the normal upper limit for AST and ALT in 11.1% and 7.4% of the patients, respectively. Initially, the level of AST was greater than that of ALT, increasing to maximum levels nine days after the onset of symptoms, then decreasing to normal levels within two weeks. Results of the biochemical tests did not differ significantly between the cases with and without hepatitis B or hepatitis C virus infection, but significantly higher elevations of AST, ALT, and G-GT were observed in patients with episodes of bleeding. Liver biopsies of two patients showed features of lobular hepatitis. Of the five fatal cases, three died of hepatic failure. It is concluded that dengue fever may cause hepatic injury and transaminase elevation similar to that in patients with conventional viral hepatitis. In epidemic or endemic areas, dengue fever infection should be considered in the differential diagnosis of hepatitis.

The prognostic factors of severe amebic liver abscess: a retrospective study of 125 cases.

One hundred twenty-five cases of amebic liver abscess were diagnosed at Chang Gung Memorial Hospital in Taiwan from January 1981 to December 1989. An analysis of possible prognostic factors for severe amebic liver abscess was done retrospectively. The majority of the patients came from the southern part of Taiwan. Severe amebic liver abscess was defined as the rupture of an abscess that was resistant to 72 hr of medical treatment, or complicated by secondary bacterial infection. The results showed significant differences between patients with severe liver abscess and those with more moderate forms of amebic liver abscess in indices such as jaundice, hemoglobin and serum bilirubin levels, and dyspnea, as well as in pulmonary changes (right diaphragm elevation, right pleural effusion) seen on chest radiographs. Those patients with diabetes mellitus also had greater evidence of severe liver abscess. Moderate cases that were treated with amebicides showed excellent responses (no mortality). Severe cases required, in addition to amebicide therapy, either percutaneous or surgical drainage of pus, especially in those patients with ruptured abscesses. Those patients with abscesses that ruptured into the thoracic cavity were treated by either thoracostomy or needle aspiration, and all were cured. Three patients died of abscess rupture into the abdominal cavity, associated with secondary bacterial infection. The overall mortality rate was 2.4%. These symptoms and signs of severe liver abscess are indicators of the need for intensive treatment such as aspiration or surgical drainage.

Prenatal and molecular diagnosis of beta-thalassemia major in Taiwan by naturally and amplified created restriction sites.

To characterize mutations rapidly in 43 patients with beta-thalassemia major in Taiwan, we utilized a method of natural and amplified created restriction site (ACRS) analysis for detection of beta-globin gene mutation. After analysis, eight different point mutations were found among 86 known chromosomes. IVS-2 nt 654 (C-->T), accounting for 40 of the 86 mutations with mutant beta-globin genes, is the most common mutation, followed by frameshift codons 41/42 (-TCTT) in 28 mutations, -28 mutation (A-->G) in 7 mutations, nonsense codon 17 (A-->T) in 5 mutations, frameshift codons 27/28 (insertion of C) in 2 mutations, IVS-1 nt 1 (G-->T) in 2 mutations, frameshift codons 71/72 (insertion of A) in 1 mutation, and IVS-1 3' end TAG-->GAG in 1 mutation. The first four mutations account for 80 of all 86 mutations of beta-thalassemia major in Taiwan. Furthermore, the beta-globin gene mutation was identified successfully in one chorionic villi biopsy for prenatal diagnosis and in specimen of blood from one patient who had received bone marrow transplantation (BMT). Complete diagnosis is possible in all of the Chinese families with beta-thalassemia in Taiwan, and the first trimester prenatal diagnosis can be achieved simply by using only 13 oligonucleotide primers and 10 restriction endonucleases. This non-radioactive assay was shown to be a rapid, sensitive, precise and safe method in detecting the mutations of beta-thalassemia in Taiwan.

Molecular basis of beta-thalassemia minor in Taiwan.

The mutations producing beta-thalassemia minor in 227 Taiwanese were studied using the method of naturally and amplified created restriction sites. beta-Thalassemia minor was caused by one beta-globin gene mutation in most of the cases (225/227); only a few cases were caused by two gene mutation (2/227). The most common type of mutation was frameshift codon 41/42 (-TCTT) (93/227), followed in descending order by the C-->T substitution at nucleotide 654 of IVS-2 (83/227), the nonsense mutation A--T at codon 17 (22/227), the A-->T mutation at position -28 of the promotor region (12/227), the frameshift codon 27/28 (+C) (6/227), the initial codon mutation (ATG-->AGG) (5/227), and one each of the codon 71/72 (+A), IVS-1 nt 1 (G-->T), IVS-1 3' end (TAG-->GAG), and nonsense codon 43. In the two cases of the two-gene mutation, one was the nt 654 mutation with Hb Kaohsiung and another one was frameshift codon 41/42 with Hb Meinung. The first four mutations accounted for more than 90% of the mutations. The C-->T substitution at the nt 654 of IVS-2 and initial codon mutation in our study had a higher incidence than in other Southeast Asia areas. Comparison of clinical data in different types of beta-thalassemia showed that there were higher MCV and MCH levels in beta (+)-thalassemia.

Sequential invasions of pancreatic pseudocysts in pancreatic tail, hepatic left lobe, caudate lobe, and spleen.

A 66-year-old male patient without a history of risk factors for pancreatitis suffered from pancreatitis and developed pseudocyst. During the course of treatment and follow-up, the pseudocyst was found to have migrated through the pancreatic tail, left hepatic lobe, caudate lobe, and spleen on abdominal sonography and computed tomography scan. Finally, emergent laparotomy was done for splenic abscess and removal of infected pseudocyst in the spleen and lesser sac of the abdomen. The patient made a full recovery after operation.

Traumatic injury among drywall installers, 1992 to 1995.

This study examined the traumatic-injury characteristics associated with one of the high-risk occupations in the construction industry--drywall installers--through an analysis of the traumatic-injury data obtained from the Bureau of Labor Statistics. An additional objective was to demonstrate a feasible and economic approach to identify risk factors associated with a specific occupation by using an existing database. An analysis of nonfatal traumatic injuries with days away from work among wage-and-salary drywall installers was performed for 1992 through 1995 using the Occupational Injury and Illness Survey conducted by the Bureau of Labor Statistics. Results from this study indicate that drywall installers are at a high risk of overexertion and falls to a lower level. More than 40% of the injured drywall installers suffered sprains, strains, and/or tears. The most frequently injured body part was the trunk. More than one-third of the trunk injuries occurred while handling solid building materials, mainly drywall. In addition, the database analysis used in this study is valid in identifying overall risk factors for specific occupations.

Ergonomic exposure assessment: an application of the PATH systematic observation method to retail workers. Postures, Activities, Tools and Handling.

This study examined biomechanical stressor variables (physical work exposures) in relation to job title, gender, and back-belt status in 134 retail store workers. The principal concerns were to quantitatively describe physical work exposures and to determine the degrees to which these quantitative variables correlated with job title and with the use of back belts. An additional objective was to assess the inter-rater reliability of the observation method. The systematic observation method employed was based on a modification of the PATH (Postures, Activities, Tools, and Handling) measurement method. Chi-square analysis indicated that the frequencies of bent or twisted postures followed the pattern of unloaders > stockers > department managers. For weight handled per lift, lower, or carry, the pattern was unloaders > department managers > stockers. The mean lifting frequencies per hour were 35.9 for department managers, 48.8 for stockers, and 137.4 for unloaders. Back-belt-wearing percentages were higher for unloaders (63%) compared with stockers (48%) and department managers (25%). Back-belt-wearing workers had higher levels of biomechanical stressor variables, including arm position, twisting, weight handled, and number of lifts per hour. Kappa statistics ranged from 0.5 to 0.63, a level of adequate or good reliability beyond chance. The method employed in this study is applicable in studies that require only fairly crude distinctions among biomechanical stressor variables. Nevertheless, this level of distinction may be sufficient when implementing intervention studies and control strategies for many material-handling-intensive jobs.

Acute lymphoblastic leukemia in one of two siblings with Alstrom syndrome.

Alstrom syndrome is a rare autosomal recessive disease; less than 60 cases have been reported. No Chinese patient with this disease has been reported previously in the literature. Here, we describe an 11-year-old Chinese boy with this condition. His elder sister also had Alstrom syndrome, and his father had non-insulin-dependent diabetes mellitus. Both siblings had degenerative retinopathy, obesity, mental retardation, perceptive hearing loss, short stature, non-insulin-dependent diabetes mellitus, nephropathy, hyperlipidemia, acanthosis nigricans, and hepatic dysfunction. The boy also developed acute lymphoblastic leukemia, which was confirmed by cytochemistry and immunophenotyping findings. He received chemotherapy and radiotherapy for the malignancy. The present case suggests that acute lymphoblastic leukemia may be coincident with or may be a previously undescribed systemic manifestation of Alstrom syndrome.

Tc99m sulfur colloid scintigraphy for detection of intrathoracic extramedullary hematopoiesis in patient with beta-thalassemia major--a case report.

Extramedullary hematopoiesis (EMH) refers to the production of blood cells outside the bone marrow and is a compensatory mechanism for bone marrow dysfunction. A 34 year-old female patient with beta thalassemia major was found to have multiple large, well-circumscribed radiopaque paravertibral mass lesions in chest radiography. Magnetic resonance imaging (MRI) of the thorax disclosed a right upper apical and two lower thoracic paraspinal mass lesions with heterogeneous isointensity on T1-weighted images and hypointensity on T2-weighted images. Because intrathoracic EMH is suspected in our case, which had obvious bone marrow dysfunction, radionuclide bone marrow scintigraphy is helpful in supporting the diagnosis. Tc99m sulfur colloid scintigraphy demonstrated three intense radioactive thoracic paraspinal mass lesions corresponding to the lesions seen on MRI. We believe whole body bone marrow scintigraphy with Tc99m sulfur colloid is the best convenient noninvasive method for supporting the diagnosis of EMH.

Thrombocytosis in children at one medical center of southern Taiwan.

Thrombocytosis in children is common, but usually without symptoms. The causes of thrombocytosis in children are considered to be mostly due to infection, trauma, surgery, blood disease, prematurity, renal disease and chronic inflammation. To evaluate the incidence and etiology of thrombocytosis of the hospitalized patients, patients who were admitted to the Pediatric Department of Kaohsiung Medical College Hospital (KMCH) from October 1996 to November 1997 were studied. There were 2910 cases studied and 220 cases (127 male and 93 female) had thrombocytosis (> or = 500 x 10(9)/L) with a rate of 7.6%. The causes of thrombocytosis are infections (49.5%), Kawasaki disease (6.4%), postsplenectomy (7.8%), blood diseases (3.7%), malignancies (3.2%), renal disorders (3.2%), prematurity (3.2%), tissue damage (4.5%), chronic inflammation (1.8%), recovery from marrow suppression (1.3%), immunologic disturbances (2.2%), essential thrombocythemia (0.5%), and miscellaneous factors (3.7%). Thrombocytosis associated with multiple, simultaneous causative factors was found in 9.0% of these cases. Thrombocytosis secondary to infectious diseases or Kawasaki disease was significantly more common in children under 2 years old. The most commonly associated infectious disease was respiratory tract infection (61.1%). There were 29 children (13.2%) presenting a platelet count of more than 800,000/mm3. However, no thrombotic complications were seen in any of the children. By far, the major cause of thrombocytosis in our cases was reactive in character. Most of the thrombocytosis cases were due to infections, inflammatory diseases, or Kawasaki disease.

Treatment results of the TPOG-NHL92 protocols for childhood non-Hodgkin's lymphomas in Taiwan: a report from the Taiwan Pediatric Oncology Group (TPOG)

A nation-wide chemotherapeutic trial for childhood non-Hodgkin's lymphoma (NHL) was conducted by the Taiwan Pediatric Oncology Group (TPOG). Four TPOG-NHL92 protocols based on stage and histology were activated in 1992: TPOG-92LD (treatment duration: 8 months) was used for localized (stages I/II) NHL with any histology, 92LB (2 years), 92SNC (5 months), and 92LC (1 year) for advanced (stages III/IV) lymphoblastic (LB), small non-cleaved cell (SNC), and large cell (LC) lymphoma, respectively. From January 1992 through June 1998, 200 children with newly diagnosed NHL from 13 member hospitals of TPOG were enrolled. There were 140 boys and 60 girls. Their ages at diagnosis ranged from 2.4 months to 18.3 years with a median of 8.2 years. There were 54 (27.3%) patients with LB, 94 (47.5%) with SNC including B-cell acute lymphoblastic leukemia (B-ALL), and 50 (25.2%) with LC. Stages I, II, III, and IV (including B-ALL) of the disease comprised 5%, 10%, 43%, and 42% of cases, respectively. There were 176 patients eligible for evaluation of treatment results. The remission rate of induction was 82.4%, induction failed in 22 (12.5%) patients, and nine patients died during induction. As of August 31, 1999, 26 patients relapsed, six died during remission, one patient developed secondary acute myelomonocytic leukemia, and 105 patients remained in continuous remission with a median remission duration of 49 months. The event-free survival (EFS) at 7 years was 63.5%, 61.5% and 65% for LB, SNC, and LC groups (P = 0.8298). The 7-year EFS for stages I/II, III, and IV of the disease was 73%, 68.9%, and 50.3% (P = 0.0212), respectively. We concluded that following the strategy of stratification of therapy, only disease stages had prognostic significance in this study. More efforts are needed to improve our treatment results.

Detection and differentiation of genotype I and III Japanese encephalitis virus in mosquitoes by multiplex reverse transcriptase-polymerase chain reaction.

Japanese encephalitis (JE) is a disease that threatens both human and animal populations in Asian countries, and the causative agent of JE, Japanese encephalitis virus (JEV), has recently changed from genotype III (GIII) to genotype I (GI). However, a test for the rapid differentiation of GI and GIII JEV is still unavailable, especially one that can be used for mosquito-based surveillance. We have designed GI- and GIII-specific primer sets for the rapid detection and differentiation of GI and GIII JEV by multiplex reverse transcriptase-polymerase chain reaction (multiplex RT-PCR). The GI-specific and GIII-specific primer sets were able to specifically amplify the target gene from GI and GIII JEV, respectively. The limitations of detection were 0.00225 and 0.225 pfu for the GI-specific and GIII-specific primers, respectively. Using a mixture of GI-specific and GIII-specific primers, the multiplex RT-PCR was able to specifically detect and differentiate GI and GIII JEV. The multiplex RT-PCR was able to successfully differentiate GI and GIII virus in JEV-infected mosquitoes. Thus, a sensitive and specific multiplex RT-PCR system for the rapid detection and differentiation of GI and GIII JEV has been developed, and this test is likely to be valuable when carrying out mosquito-based JEV surveillance.

In vivo modulation of polo-like kinases supports a key role for PLK2 in Ser129 α-synuclein phosphorylation in mouse brain.

α-Synuclein is the major component of Lewy bodies. α-Synuclein phosphorylated at Ser 129 (Phospho-α-Syn) is the most common synuclein modification observed in Parkinson's disease pathology and transgenic animal models. Polo-like kinase 2 (PLK2) was previously proposed as an important kinase in α-synuclein phosphorylation at Ser129. To better understand the role of PLK2 in α-synuclein phosphorylation in vivo, we further evaluated the effect of PLK2 genetic knockdown and pharmacological inhibition on Phospho-α-Syn levels in different brain regions of PLK2 knockout (KO), heterozygous (Het) and wild-type (WT) mice. Whereas PLK2 knockdown had no effect on Total-α-synuclein brain levels, it resulted in a gene-dosage dependent, albeit incomplete, reduction of endogenous Phospho-α-Syn levels in all brain regions investigated. No compensatory induction of other α-synuclein kinases (PLK3, casein kinase-2, G-protein-coupled receptor kinase 5 (GRK5) and GRK6) was observed at the mRNA level in the PLK2 KO mouse brain. To determine whether increased activity of another PLK family member is responsible for the residual Phospho-α-Syn levels in the PLK2 KO mouse brain, the pan-PLK inhibitor BI 2536 was tested in PLK2 KO mice. Whereas BI 2536 reduced Phospho-α-Syn levels in WT mice, it did not further reduce the residual endogenous Phospho-α-Syn levels in PLK2 KO and Het mice, suggesting that a kinase other than PLK1-3 accounts for the remaining PLK inhibitor-resistant pool in the mouse brain. Moreover, PLK3 KO in mice had no effect on both Total- and Phospho-α-Syn brain levels. These results support a significant role for a PLK kinase in phosphorylating α-synuclein at Ser129 in the brain, and suggest that PLK2 is responsible for this activity under physiological conditions.