Organometallic‐Mediated Radical Polymerization: Developing Well‐Defined Complexes for Reversible Transition Metal‐Alkyl Bond Homolysis

Organometallic‐mediated radical polymerization (OMRP) has emerged as a powerful new class of living controlled radical polymerization. In order to fulfill its potential in the polymerization of vinyl acetate (VOAc) and other challenging monomers, the effects of ancillary ligands on the metal‐alkyl bond dissociation energy in OMRP reagents must be thoroughly explored. Recent results investigating structure‐activity relationships in well‐defined cobalt, iron and chromium complexes will be discussed. The involvement of radical intermediates in oxidative addition of secondary alkyls for catalytic cross‐coupling reactions catalyzed by first row transition metals will also be examined for relevant design concepts.

     

A Phenotypic Approach for IUIS PID Classification and Diagnosis: Guidelines for Clinicians at the Bedside

The number of genetically defined Primary Immunodeficiency Diseases (PID) has increased exponentially, especially in the past decade. The biennial classification published by the IUIS PID expert committee is therefore quickly expanding, providing valuable information regarding the disease-causing genotypes, the immunological anomalies, and the associated clinical features of PIDs. These are grouped in eight, somewhat overlapping, categories of immune dysfunction. However, based on this immunological classification, the diagnosis of a specific PID from the clinician’s observation of an individual clinical and/or immunological phenotype remains difficult, especially for non-PID specialists. The purpose of this work is to suggest a phenotypic classification that forms the basis for diagnostic trees, leading the physician to particular groups of PIDs, starting from clinical features and combining routine immunological investigations along the way. We present 8 colored diagnostic figures that correspond to the 8 PID groups in the IUIS Classification, including all the PIDs cited in the 2011 update of the IUIS classification and most of those reported since.     

Association of IL28B SNP With Progression of Egyptian HCV Genotype 4 Patients to End Stage Liver Disease

Background

IL28B single nucleotide polymorphisms (SNPs) play important roles in the management of hepatitis C virus (HCV) infections and are strongly associated with spontaneous and treatment-induced HCV clearance.

Objectives

In the present study, the association between IL28B variants and the progression of HCV infection in Egyptian patients infected with type 4a virus will be examined.

Patients and Methods

Frequencies of the protective genotype C/C of SNP, rs12979860 were determined in healthy subjects, spontaneous resolvers, and chronic HCV type 4 patients with low F scores and in patients with end stage liver disease (ESLD). This study included a total of 404 subjects. Patients infected with HCV type 4a (n = 304) were divided into; chronic hepatitis C (CHC) with low F scores (CHC, n = 110), end stage liver disease (n = 110), liver cirrhosis (LC) (n = 35) and hepatocellular carcinoma (HCC) patients (n = 75), spontaneous resolvers of HCV infection (n = 84) were also included. A healthy group representing the Egyptian population (n = 100) was also included in the genotyping of IL28B. The later was typed via a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay analysis on purified genomic DNA extracted from all individuals.

Results

A significant increase (P < 0.0005) was observed in frequencies of IL-28B rs12979860 C/C genotypes in the healthy population, than in the CHC, LC and HCC groups (C/C = 48%, 13%, 0%.and 0% respectively). On the other hand the C/C genotype was significantly higher (P < 0.0005) in spontaneous resolvers than in healthy subjects. A comparable significant increase in the frequency of C/T allele accompanied by mild elevation of T/T allele frequency, were detected along the progression towards ESLD.

Conclusions

Genotype C/C is associated with viral clearance during acute infection. The sharp decline in the C/C genotype from healthy to CHC subjects and the total absence of the C/C genotype in ESLD suggests a central role of this genotype against HCV disease progression.     

Human papillomavirus subtype 16 is common in Pakistani women with cervical carcinoma.

INTRODUCTION: Human papillomavirus (HPV) is recognized as a major causative agent for cervical carcinomas. Based on their oncogenic potential, HPV subtypes have been divided into high- and low-risk. In Pakistan, screening for HPV in female patients is not commonly practiced, and as a consequence, the degree of HPV prevalence and its correlation with cervical cancer is unknown. OBJECTIVE: In this study, we have attempted to estimate the prevalence of HPV infection, and also the HPV subtype profile, among Pakistani women with cervical cancer from varied geographical, racial, and social backgrounds within Pakistan. METHODOLOGY: Women visiting two tertiary care hospitals in Karachi, diagnosed with carcinoma of the cervix within the past 15 years, were analyzed for HPV subtypes in their cancer specimens. Retrospectively, 60 paraffin-embedded cervical cancer biopsies were examined for the presence of HPV DNA. After DNA extraction from these samples, polymerase chain reaction (PCR) was used to amplify the HPV L1 gene using the consensus (general) primers, and primers specific for subtypes 16 and 18. RESULTS: Of the 60 samples analyzed, only one sample was HPV negative; the rest of the samples were positive for the presence of HPV. Of the 59 HPV positive samples, 56 showed the presence of HPV16 and one sample was positive for HPV18; HPV subtype could not be determined in two samples. CONCLUSION: Our results show a strong relationship between HPV infection and cervical cancer among Pakistani women. These results underscore the need to implement regular HPV screening for Pakistani women. An early diagnosis of HPV infection will allow better health management to reduce the risk of developing cervical cancer.     

Clinical trial of two short-course (6-month) regimens and a standard regimen (12-month) chemotherapy in retreatment of pulmonary tuberculosis in Pakistan. Results 18 months after completion of treatment (Lahore Tuberculosis Study)

This study compared the efficacy and tolerability of two 6-month daily regimens of isoniazid and rifampin in combination with either pyrazinamide or ethambutol (RHZ and RHE regimens) against a standard daily regimen of streptomycin, isoniazid, and ethambutol (SHE regimen) given for 6 months followed by isoniazid and ethambutol for an additional 6 months. Only previously treated sputum positive patients suffering from active pulmonary tuberculosis were entered into the study. Three hundred and fifty-eight patients were admitted to the study and 267 (75%) completed chemotherapy. Eighty-five percent of RHZ-regimen and 82% of RHE-regimen patients achieved sputum culture negativity compared to 55% of patients in SHE regimen. Successfully treated patients were followed up for 18 months, and among these, all 3 treatment regimens showed broadly similar levels of culture negativity at the end of the follow-up period. Final therapeutic outcome was based on sputum culture results obtained throughout the follow-up period, and no statistically significant difference in relapse rate was noticed in the 3 regimens. Severe drug intolerance necessitated discontinuation of therapy in only 2 patients.     

Surgical Treatment of Hydatidothorax Series of 79 Cases

Objective: A retrospective review of 79 cases of ruptured intrapleural pulmonary hydatid cysts. We analyse and evaluate our experience in the surgical treatment of this complication.

Materials and Methods: In a ten-year period, from 1990 to 1999, 79 patients were operated on in our service for intrapleural rupture of a pulmonary hydatid cyst. There were 51 males and 28 females with a mean age of 35.4 years. The diagnosis was established on the basis of different clinical signs and imaging studies.

Surgical approach consisted of a posterolateral thoracotomy in all cases. After decortication, different procedures were performed on the pulmonary lesions according to the importance of lung destruction.

Results: Radical resections were done in 48 cases, including lobectomies (15), segmentectomies (33) and conservative treatment: simple capitonnage and bronchial fistula closure (31).

Postoperative complications occurred in 8 cases (10.1%), including one pyothorax, one haemothorax, one prolonged air leak, two pneumonias and two wound infections.

There was one postoperative death, by respiratory failure. Ninety-five percent (95%) of patients were free of recurrence of thoracic hydatid disease in a follow-up ranging from 1 to 10 years (mean: 5.4 years).

Conclusion: Hydatid cysts of the lung should be treated before complications occur, particularly intrapleural rupture because it considerably increases morbidity.     

Treatment of Hepatitis C Virus Infection in Children Less than 12 Years of Age in Developing Countries

The treatment of hepatitis c virus (HCV) infection in children is difficult as few options are available. The standard therapy is combination pegylated interferon (PEG–IFN) α-2a or 2b and ribavirin, and the duration of therapy depends on HCV genotype. New oral drug therapies available for adults have still not been approved for treatment in children. Here, we review the causes of HCV infection in children, the therapeutic options for children, and the side effects of these treatments. The problems faced by physicians managing HCV infection in children less than 12 years of age in a developing country are also discussed.