Structural analysis of potato starch transformation during high-energy ball-milling: Oxygen and humidity content effects.

High Energy Ball-Milling (HEBM) modifies starchs' granule morphology, physicochemical properties, and chemical structure. However, understanding how the HEBM changes the starch chemical structure is necessary to control these modifications. Therefore, this study aimed to investigate the changes in potato starch's long- and short-range molecular order during HEBM at different environmental conditions such as oxygen (Air) and humidity content. Due to the correlation between the starch modification and the energy supplied (Esupp) by the HEBM, Burgio's equation was used to calculate this energy. The starch transformation was followed by X-ray diffraction, Fourier Transform-Infrared Spectroscopy, and Raman spectroscopy. A Principal Component Analysis (PCA) was conducted to reduce the HEBM variables. PAC analysis demonstrated that the different oxygen-humidity conditions do not affect the HEBM of potato starch. Based on the starch chemical structure transformation correlated with Esupp during HEBM, four stages were observed: orientation, modification, mechanolysis, and over-destruction. It was identified for the first time that at low milling energy (<1.5 kJ/g, orientation stage), the glycosidic rings change their orientation, and starch-water interaction increases while the starch's organization reduces. Ergo, the potato starch could be more susceptible to chemical modifications during the first two stages.

Acculturation and breastfeeding on the United States-Mexico border.

Previous studies have demonstrated a strong association between breastfeeding incidence and ethnic background, indicating the presence of strong cultural influences on infant-feeding patterns within ethnic groups. This study analyzed the relationship of acculturation into the United States, one aspect of ethnicity, to the initiation of breastfeeding among a sample of 213 women recruited approximately 2 months prenatally in the United States-Mexico border city of Brownsville, Texas. An in-depth, structured interview was conducted at that time (n = 213), at the time of birth (n = 207), and 2 to 3 weeks postnatally (n = 206). In addition, male partners of the mothers were interviewed prenatally when available (n = 119). Acculturation scores and demographic characteristics were tested relative to breastfeeding initiation. The degree of acculturation, age, and marital status were associated significantly with breastfeeding initiation (with breastfeeding continued at 2 to 3 weeks postnatally), but occupational status, education, and income were not. Breastfeeding incidence was highest among older, married, or low-acculturated, Anglo mothers. These data suggest that women being assimilated into the United States are inhibited in the initiation of breastfeeding. These findings suggest that to be successful, intervention programs to increase breastfeeding incidence must consider the cultural adaptation of different groups as they meld with the larger population.

Differences in biologic maturation, sexual behavior, and sexually transmitted disease between adolescents with and without cervical intraepithelial neoplasia.

Because several cofactors may influence the development of cervical intraepithelial neoplasia (CIN) in young women, we compared differences in behaviors (sexual activity, contraception, and cigarette use), sexually transmitted disease (STD) infection rates (Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, and herpes simplex virus), and cervical maturation (age of menarche and percentage of cervical ectopy) in groups of sexually active female adolescents with and without CIN. Those with CIN were compared with three non-CIN groups: (1) teenagers who were referred to a teen colposcopy clinic but had no evidence of CIN (high-risk group), (2) teenagers seen at a gynecology clinic without STD symptoms (asymptomatic group), and (3) teenagers seen at the gynecology clinic with STD symptoms (symptomatic group). The percentage of cervical ectopy was measured by colpophotography. Subjects with CIN had more lifetime sexual partners than the asymptomatic group (p less than 0.001) and were more likely to smoke cigarettes than either gynecology clinic group (p less than 0.01). No differences in behaviors existed between the CIN and high-risk groups. The mean age of menarche in those with CIN was 1 year older than all three non-CIN groups (p less than 0.05), and those with CIN had a greater area of ectopy than those without CIN (p less than 0.02). Those with CIN were more likely to have a past or present history of C. trachomatis infection than the two gynecology clinic groups; no difference was found between the CIN and high-risk groups. We conclude that cofactors such as smoking, sexual promiscuity, and C. trachomatis infection may influence cervical vulnerability. However, cervical biologic immaturity is an important risk factor for development of CIN in adolescent girls.

PIP: From April-September 1986, researchers asked all 14-19 year old females attending the University of California at San Francisco's Teen Colposcopy Clinic to take part in an epidemiologic study of risk factors for cervical intraepithelial neoplasia (CIN). The 4 comparison groups consisted of a CIN group, a high risk group (external warts or abnormal Pap smear, no CIN, similar behavioral risk factors as CIN group), as asymptomatic group, and a symptomatic group (negative Pap smears and lower genital tract infection complaints). The CIN group was more likely to smoke or have smoked than the asymptomatic and symptomatic groups (p.01) and to use oral contraceptives than the asymptomatic group (p.02). In addition, patients with CIN had more lifetime sexual partners than did the asymptomatic group (p.001). The teens in the CIN group reached menarche on average 1 year later than did those in any of the comparison groups (p.05). This also had a greater area of ectopy than the other 3 groups (p.02). External genital warts occurred more often in the CIN group than in either the asymptomatic or symptomatic groups (p.001). Further, the CIN and high risk groups were more likely to have had any sexually transmitted disease than the asymptomatic (p.001) or symptomatic (p.01) groups. In addition, chlamydiosis occurred more often in the CIN group than in the asymptomatic (p.001) or symptomatic groups (p.03). The results indicate that cervical biologic immaturity may play an important role in development of CIN in adolescents. They also showed that CIN patients had more ectopy than the others thereby demonstrating that cervical biologic immaturity may rend the epithelium vulnerable to human papilloma virus invasion and neoplastic change.