Myoglobin Cast Nephropathy Diagnosed on Renal Biopsy in a Patient Treated for Malarial Infection.

Myoglobin cast nephropathy occurs in cases of acute renal injury in which large amounts of myoglobin accumulate in the renal tubules, presenting as muscle pain, reddish-brown urine, and elevated creatine kinase levels. Our case describes a 60-year-old male who came to the emergency department with fevers, mild abdominal pain, and constitutional symptoms one day after returning to the United States from a trip to Nigeria. Initial workup demonstrated an acute kidney injury and elevated aminotransferase levels and the patient was started onatovaquone-proguanil for possible malaria given a recent diagnosis in Nigeria. Two days later, the patient was found to have rhabdomyolysis, resulting in a renal biopsy that showed myoglobin cast nephropathy. Previous literature has suggested mechanisms for the development of rhabdomyolysis in malarial infection, including inflammatory processes, direct effect of parasite accumulation, and drug-induced toxicity. Our case further implicates antimalarial therapy as a cause of rhabdomyolysis and increases awareness of myoglobin cast nephropathy as a potential complication of malaria.

Flea-Borne Typhus Presenting with Acalculous Cholecystitis and Severe Anemia.

Background: Flea-borne typhus (FBT), an uncommon illness in the United States, typically presents as a high continuous fever with commonly associated symptoms including headache, myalgias, and rashes on the trunk and extremities. Patients infected with FBT may also present with atypical symptoms. As such, the combination of its relatively low incidence in the United States coupled with its variability in associated symptoms poses a diagnostic challenge for clinicians; early empiric treatment with doxycycline is warranted prior to a definitive diagnosis to reduce the risk of damage to vital organs. Case Report. This case describes a 54-year-old male who presented to an emergency room in Houston, Texas, with one week of constant right upper quadrant abdominal pain and fevers up to 40°C. The patient was initially diagnosed with Grade III severe acute cholangitis after abdominal ultrasound revealed gallbladder sludge and wall thickening without ductal dilatation, but a subsequent endoscopic retrograde cholangiopancreatography was unremarkable. Following intermittent fevers and worsening anemia, the patient was started on oral doxycycline for atypical infection, and an infectious disease workup subsequently returned a positive titer for Rickettsia typhi. He experienced rapid symptomatic and clinical improvement, and the patient was discharged home with a final diagnosis of flea-borne typhus. Conclusion: Albeit uncommon, the presentation of this patient's symptoms and final diagnosis of flea-borne typhus demonstrates the importance of (1) keeping atypical infections such as FBT in the differential diagnosis and (2) beginning empiric treatment to prevent damage to vital organs if suspicion of FBT is high.

The E3 ligase Poe promotes Pericentrin degradation.

Centrosomes are essential parts of diverse cellular processes, and precise regulation of the levels of their constituent proteins is critical for their function. One such protein is Pericentrin (PCNT) in humans and Pericentrin-like protein (PLP) in Drosophila. Increased PCNT expression and its protein accumulation are linked to clinical conditions including cancer, mental disorders, and ciliopathies. However, the mechanisms by which PCNT levels are regulated remain underexplored. Our previous study demonstrated that PLP levels are sharply down-regulated during early spermatogenesis and this regulation is essential to spatially position PLP on the proximal end of centrioles. We hypothesized that the sharp drop in PLP protein was a result of rapid protein degradation during the male germ line premeiotic G2 phase. Here, we show that PLP is subject to ubiquitin-mediated degradation and identify multiple proteins that promote the reduction of PLP levels in spermatocytes, including the UBR box containing E3 ligase Poe (UBR4), which we show binds to PLP. Although protein sequences governing posttranslational regulation of PLP are not restricted to a single region of the protein, we identify a region that is required for Poe-mediated degradation. Experimentally stabilizing PLP, via internal PLP deletions or loss of Poe, leads to PLP accumulation in spermatocytes, its mispositioning along centrioles, and defects in centriole docking in spermatids.

Prospective Comparison of Geriatric Assessment and Provider's Assessment of Older Adults With Metastatic Breast Cancer in the Community.

BACKGROUND: Geriatric assessment (GA) is recommended for evaluating fitness of an older adult with cancer. Our objective was to prospectively evaluate the gaps that exist in the assessment of older adults with metastatic breast cancer (OA-MBC) in community practices (CP). METHODS: Self-administered GA was compared to provider's assessment (PA) of patients living with MBC aged ≥65 years treated in CP Providers were blinded to the GA results until PA was completed. McNemar's test was used to detect differences between PA and GA. RESULTS: One hundred patients were enrolled across 9 CP (median age 73.9). Geriatric assessment detected a total of 356 abnormalities in 96 patients; of which, 223 required interventions. African American and widowed/single patients were more likely to have abnormalities identified by GA. On average, across 100 patients, PA did not detect 25.5% of GA-detected abnormalities, mostly in functional status, social support, nutrition, and cognition. These differences were less pronounced among providers with more clinical experience. Patients with abnormal Timed Up and Go tests more likely had additional abnormalities in other domains, and more abnormalities that were not identified by PA. Providers were "surprised" by GA results in 33% of cases, mainly with cognitive or social support findings, and reported plans for management change for 39% of patients based on GA findings. CONCLUSIONS: Including a GA in the care of OA-MBC in CP is beneficial for the detection of multiple abnormalities not detected by routine PA.

Fascetto interacting protein ensures proper cytokinesis and ploidy.

Cell division is critical for development, organ growth, and tissue repair. The later stages of cell division include the formation of the microtubule (MT)-rich central spindle in anaphase, which is required to properly define the cell equator, guide the assembly of the acto-myosin contractile ring and ultimately ensure complete separation and isolation of the two daughter cells via abscission. Much is known about the molecular machinery that forms the central spindle, including proteins needed to generate the antiparallel overlapping interzonal MTs. One critical protein that has garnered great attention is the protein regulator of cytokinesis 1, or Fascetto (Feo) in Drosophila, which forms a homodimer to cross-link interzonal MTs, ensuring proper central spindle formation and cytokinesis. Here, we report on a new direct protein interactor and regulator of Feo we named Feo interacting protein (FIP). Loss of FIP results in a reduction in Feo localization, rapid disassembly of interzonal MTs, and several defects related to cytokinesis failure, including polyploidization of neural stem cells. Simultaneous reduction in Feo and FIP results in very large, tumorlike DNA-filled masses in the brain that contain hundreds of centrosomes. In aggregate, our data show that FIP acts directly on Feo to ensure fully accurate cell division.

Bridging centrioles and PCM in proper space and time.

Throughout biology, specifying cellular events at the correct location and time is necessary for ensuring proper function. The formation of robust microtubule organizing centers (MTOCs) in mitosis is one such event that must be restricted in space to centrosomes to prevent ectopic MTOC formation elsewhere in the cell, a situation that can result in multipolar spindle formation and aneuploidy. The process of reaching maximum centrosome MTOC activity in late G2, known as centrosome maturation, ensures accurate timing of nuclear envelope breakdown and proper chromosome attachment. Although centrosome maturation has been recognized for over a century, the spatial and temporal regulatory mechanisms that direct MTOC activation are poorly understood. Here, we review Sas-4/CPAP, Asterless/Cep152, Spd-2/Cep192, and PLP/Pericentrin, a group of proteins we refer to as 'bridge' proteins that reside at the surface of centrioles, perfectly positioned to serve as the gatekeepers of proper centrosome maturation at the perfect place and time.

A centrosomal scaffold shows some self-control.

The scaffolding protein AKAP350A is known to localize to the centrosome and the Golgi, but the molecular details of its function at the centrosome remain elusive. Using structure-function analyses, protein interaction assays, and super-resolution microscopy, Kolobova et al. now identify AKAP350A's specific location and protein partners at the centrosome. The authors further define an autoregulatory mechanism that likely controls AKAP350A's ability to nucleate microtubule growth.

Myt1 inhibition of Cyclin A/Cdk1 is essential for fusome integrity and premeiotic centriole engagement in Drosophila spermatocytes.

Regulation of cell cycle arrest in premeiotic G2 phase coordinates germ cell maturation and meiotic cell division with hormonal and developmental signals by mechanisms that control Cyclin B synthesis and inhibitory phosphorylation of the M-phase kinase, Cdk1. In this study, we investigated how inhibitory phosphorylation of Cdk1 by Myt1 kinase regulates premeiotic G2 phase of Drosophila male meiosis. Immature spermatocytes lacking Myt1 activity exhibit two distinct defects: disrupted intercellular bridges (fusomes) and premature centriole disengagement. As a result, the myt1 mutant spermatocytes enter meiosis with multipolar spindles. These myt1 defects can be suppressed by depletion of Cyclin A activity or ectopic expression of Wee1 (a partially redundant Cdk1 inhibitory kinase) and phenocopied by expression of a Cdk1F mutant defective for inhibitory phosphorylation. We therefore conclude that Myt1 inhibition of Cyclin A/Cdk1 is essential for normal fusome behavior and centriole engagement during premeiotic G2 arrest of Drosophila male meiosis. The novel meiotic functions we discovered for Myt1 kinase are spatially and temporally distinct from previously described functions of Myt1 as an inhibitor of Cyclin B/Cdk1 to regulate G2/MI timing.

Dual phosphorylation of cdk1 coordinates cell proliferation with key developmental processes in Drosophila.

Eukaryotic organisms use conserved checkpoint mechanisms that regulate Cdk1 by inhibitory phosphorylation to prevent mitosis from interfering with DNA replication or repair. In metazoans, this checkpoint mechanism is also used for coordinating mitosis with dynamic developmental processes. Inhibitory phosphorylation of Cdk1 is catalyzed by Wee1 kinases that phosphorylate tyrosine 15 (Y15) and dual-specificity Myt1 kinases found only in metazoans that phosphorylate Y15 and the adjacent threonine (T14) residue. Despite partially redundant roles in Cdk1 inhibitory phosphorylation, Wee1 and Myt1 serve specialized developmental functions that are not well understood. Here, we expressed wild-type and phospho-acceptor mutant Cdk1 proteins to investigate how biochemical differences in Cdk1 inhibitory phosphorylation influence Drosophila imaginal development. Phosphorylation of Cdk1 on Y15 appeared to be crucial for developmental and DNA damage-induced G2-phase checkpoint arrest, consistent with other evidence that Myt1 is the major Y15-directed Cdk1 inhibitory kinase at this stage of development. Expression of non-inhibitable Cdk1 also caused chromosome defects in larval neuroblasts that were not observed with Cdk1(Y15F) mutant proteins that were phosphorylated on T14, implicating Myt1 in a novel mechanism promoting genome stability. Collectively, these results suggest that dual inhibitory phosphorylation of Cdk1 by Myt1 serves at least two functions during development. Phosphorylation of Y15 is essential for the premitotic checkpoint mechanism, whereas T14 phosphorylation facilitates accumulation of dually inhibited Cdk1-Cyclin B complexes that can be rapidly activated once checkpoint-arrested G2-phase cells are ready for mitosis.

Smoking adversely affects survival in acute myeloid leukemia patients.

Smoking adversely affects hematopoietic stem cell transplantation outcome. We asked whether smoking affected outcome of newly diagnosed acute myeloid leukemia (AML) patients treated with chemotherapy. Data were collected on 280 AML patients treated with high-dose cytarabine and idarubicin-containing regimens at Roswell Park Cancer Institute who had smoking status data at diagnosis. Patients' gender, age, AML presentation (de novo vs. secondary), white blood cell (WBC) count at diagnosis, karyotype and smoking status (never vs. ever) were analyzed. Among the 161 males and 119 females with a median follow-up of 12.9 months, 101 (36.1%) had never smoked and 179 (63.9%) were ever smokers. The proportion of patients between never and ever smokers was similar to respect to age, AML presentation, WBC count at diagnosis or karyotype based on univariate analysis of these categorical variables. Never smokers had a significantly longer overall survival (OS) (60.32 months) compared to ever smokers (30.89; p = 0.005). In multivariate analysis incorporating gender, age, AML presentation, WBC count, karyotype and smoking status as covariates, age, karyotype and smoking status retained prognostic value for OS. In summary, cigarette smoking has a deleterious effect on OS in AML.

Can decreasing smoking prevalence reduce leukemia mortality?

Previous studies have demonstrated a modest association between smoking and leukemia particularly for myeloid disorders. Our objective was to examine whether changing trends in cigarette smoking prevalence nationally and within selected states parallel similar trends in mortality from leukemia. Trends in national smoking rates were correlated with trends in leukemia mortality rates obtained from the Centers for Disease Control and Prevention and the Surveillance Epidemiology and End Results registry, respectively. State-specific correlations were assessed from 1984 to 2004 using smoking prevalence data from the Behavioral Risk Factor Surveillance System and leukemia mortality data from National Vital Statistics System. Correlations were computed using the Spearman rank correlation coefficient. Leukemia mortality decreased overall in the United States in parallel with decreased smoking. Analyzed on a state-specific basis, leukemia mortality decreased in states where smoking rates declined markedly but remained unchanged where smoking prevalences were relatively stable. The findings suggest that declining rates of leukemia mortality are associated with changing patterns of smoking behavior.

Metachronous and synchronous presentation of acute myeloid leukemia and lung cancer.

Smoking is associated with both acute myeloid leukemia (AML) and lung cancer. We therefore searched our database for concomitant presentation of AML and lung cancer. Among 775 AML cases and 5225 lung cancer cases presenting to Roswell Park Cancer Institute between the years January 1992 and May 2008 we found 12 (1.5% of AML cases; 0.23% of lung cancer cases) cases (seven metachronous and five synchronous) with AML and lung cancer. All but one patient were smokers. There were no unique characteristic of either AML or lung cancer in these patients. Nine patients succumbed to AML, one died from an unrelated cause while undergoing treatment for AML, one died of lung cancer and one patient is alive after allogeneic transplantation for AML. In summary, this study supports the need for effective smoking cessation programs.

Prognosis of occult breast carcinoma presenting as isolated axillary nodal metastasis.

Axillary metastasis from an occult breast carcinoma is an uncommon presentation and presents a therapeutic dilemma. The objective of this study is to describe the presenting clinical features, management approach and treatment outcomes for occult breast carcinoma. We conducted a retrospective review of patients who presented with axillary nodal metastases from an occult breast carcinoma between 1997 and 2004 at the Roswell Park Cancer Institute; 2,150 patients were diagnosed and treated for breast cancer during this period. After excluding stage I and IV patients, we identified 642 who had disease metastatic to lymph nodes, 10 of these had no primary tumor in the breast despite a thorough evaluation including bilateral mammography and breast ultrasound. Of these, 7 had undergone breast magnetic resonance imaging as well. All patients underwent axillary nodal dissection. The breast was managed with radiotherapy alone in 8 patients, wide local excision with radiation therapy in 1 patient and 1 patient underwent mastectomy. No patient had a recurrence with a median 57 months of follow-up. Breast conservation with radiation therapy alone can be considered as a management option for women with occult breast cancer presenting with axillary nodal metastasis.